Dominique Andree Yette Caugant

• Al-Kershi, Lamia; Majeed, Zeina Abdel; Bakri, Deema Al; Odeh, Aseel; Gunaid, Magid Al & Al-Qaseer, Rund [Show all 19 contributors for this article] (2026). Second-year sentinel surveillance of bacterial meningitis in Jordan, Egypt, and Iraq: year 2 findings from the MenMap Network (2024–2025). IJID Regions. 21. doi: 10.1016/j.ijregi.2026.100984. Full text in Research Archive
• Børud, Bente; Witsø, Anne; Ngam-Asra, Nadjioroum; Antoinette, Mbailamem Demian; Djimtola, Djimtebaye & Halgue, Haoua Oumar [Show all 10 contributors for this article] (2026). Direct whole-genome sequencing of clinical specimens highlights the emergence of Neisseria meningitidis ST-10217 in Chad. International Journal of Infectious Diseases. ISSN 1201-9712. 170, p. 1–8. doi: 10.1016/j.ijid.2026.108916. Full text in Research Archive
• Al-Kershi, Lamia; Bakri, Deema Al; Majeed, Zeina Abdel; Khudair, Sara Abu; Gunaid, Magid Al & Caugant, Dominique Andree Yette [Show all 23 contributors for this article] (2026). Strengthening regional surveillance: MenMap Network’s year 1 findings on bacterial meningitis in Jordan, Egypt, and Iraq (2023-2024). IJID Regions. 19, p. 1–7. doi: 10.1016/j.ijregi.2026.100896. Full text in Research Archive
• Brynildsrud, Ola Brønstad; Gjerdrum, Hilde Synnøve Vollan; Berg, Einar Sverre; Wester, Astrid Louise & Caugant, Dominique Andree Yette (2026). Evolutionary dynamics and virulence factor variability in invasive Streptococcus pyogenes in Norway, 2017-2023. mSphere. 11(3), p. 1–20. doi: 10.1128/msphere.00775-25. Full text in Research Archive
• Borrow, Ray; Caugant, Dominique Andree Yette; Clark, Stephen A.; Dinleyici, Ener Çagri; Hall, Ian & Harrison, Lee H. [Show all 13 contributors for this article] (2025). Current global trends in meningococcal disease control, risk groups and vaccination: Consensus of the Global Meningococcal Initiative. Journal of Infection. ISSN 0163-4453. 91(5), p. 1–8. doi: 10.1016/j.jinf.2025.106635. Full text in Research Archive
• Alfsnes, Kristian; Osnes, Magnus Nygård; Gilboe, Hanne Margrethe; Eldholm, Vegard & Caugant, Dominique Andree Yette (2025). Genome analysis of Neisseria gonorrhoeae in Norway, 2016–2023, reveals shifting epidemiology in the wake of the COVID-19 pandemic. Microbial Genomics. 11(9). doi: 10.1099/mgen.0.001479. Full text in Research Archive Show summary

  The incidence of gonorrhoea has increased significantly in Norway over the past 10 years. The emergence of antimicrobial resistance and potential for increased rates of future treatment failure make epidemiological surveillance of Neisseria gonorrhoeae a top priority. Here, we combine epidemiological data and genomic analyses of isolates from cases in Norway between January 2016 and May 2023 to identify genomic clusters and antimicrobial resistance patterns. We describe how the epidemiology of N. gonorrhoeae has changed before and after the COVID-19 pandemic and the lockdown restrictions of the Norwegian society. A total of 4,096 isolates, representing 39% of all the cases recorded by the Norwegian Surveillance System for Communicable Diseases, were analysed by whole-genome sequencing. Forty-one clusters, 12 of which encompassed more than 100 isolates, were identified. As seen in other countries, the lockdown of society in 2020–2021 led to a dramatic reduction in the cases of gonorrhoea. With the lifting of the restrictions, one cluster, dominated by sequence type 1580, rapidly expanded among young, heterosexual men and women. A significant increase in the fraction of female patients was observed through the study period. An increase in isolates resistant to azithromycin was observed throughout the study period, while the proportion of ciprofloxacin and cefixime resistance remained stable. A single ceftriaxone-resistant isolate was identified.

• Lucidarme, Jay; Deghmane, Ala-Eddine; Sharma, Shalabh; Meilleur, Courtney; Eriksson, Lorraine & Mölling, Paula [Show all 34 contributors for this article] (2025). Umrah- and travel-associated meningococcal disease due to multiple serogroup W ST-11 sub-strains pre-Hajj 2024. Journal of Infection. ISSN 0163-4453. 91(4). doi: 10.1016/j.jinf.2025.106558. Full text in Research Archive
• Skaare, Dagfinn; Anthonisen, Inger Lill; Nermin, Zecic; Jenkins, Andrew John; Caugant, Dominique Andree Yette & Ranheim, Trond Egil [Show all 8 contributors for this article] (2025). Genomic profiling of cefotaxime-resistant Haemophilus influenzae from Norway and Sweden reveals extensive expansion of virulent multidrug-resistant international clones. Frontiers in Microbiology. 16. doi: 10.3389/fmicb.2025.1601390. Full text in Research Archive
• Borrow, Ray; Campbell, Helen; Caugant, Dominique Andree Yette; Cherkaoui, Abdessalam; Claus, Heike & Deghmane, Ala-Eddine [Show all 22 contributors for this article] (2024). Global Meningococcal Initiative: Insights on antibiotic resistance, control strategies and advocacy efforts in Western Europe. Journal of Infection. ISSN 0163-4453. 89(6), p. 1–8. doi: 10.1016/j.jinf.2024.106335. Full text in Research Archive
• Sharew, Bekele; Moges, Feleke; Yismaw, Gizachew; Mihret, Adane; Lobie, Tekle Airgecho & Abebe, Wondwossen [Show all 11 contributors for this article] (2024). Molecular epidemiology of Streptococcus pneumoniae isolates causing invasive and noninvasive infection in Ethiopia. Scientific Reports. 14, p. 1–10. doi: 10.1038/s41598-024-72762-9. Full text in Research Archive Show summary

  Streptococcus pneumoniae, a medically important opportunistic bacterial pathogen of the upper respiratory tract, is a major public health concern, causing a wide range of pneumococcal illnesses, both invasive and noninvasive. It is associated with significant global morbidity and mortality, including pneumonia, meningitis, sepsis, and acute otitis media. The major purpose of this study was to determine the molecular epidemiology of Streptococcus pneumoniae strains that cause invasive and noninvasive infections in Ethiopia. A prospective study was undertaken in two regional hospitals between January 2018 and December 2019. Whole-genome sequencing was used to analyze all isolates. Serotypes and multilocus sequence types (MLST) were derived from genomic data. The E-test was used for antimicrobial susceptibility testing. Patient samples obtained 54 Streptococcus pneumoniae isolates, 33 from invasive and 21 from noninvasive specimens. Our findings identified 32 serotypes expressed by 25 Global Pneumococcal Sequence Clusters (GPSCs) and 42 sequence types (STs), including 21 new STs. The most common sequence types among the invasive isolates were ST3500, ST5368, ST11162, ST15425, ST15555, ST15559, and ST15561 (2/33, 6% each). These sequence types were linked to serotypes 8, 7 C, 15B/C, 16 F, 10 A, 15B, and 6 A, respectively. Among the noninvasive isolates, only ST15432, associated with serotype 23 A, had numerous isolates (4/21, 19%). Serotype 14 was revealed as the most resistant strain to penicillin G, whereas isolates from serotypes 3, 8, 7 C, and 10 A were resistant to erythromycin. Notably, all serotype 6 A isolates were resistant to both erythromycin and penicillin G. Our findings revealed an abnormally significant number of novel STs, as well as extremely diversified serotypes and sequence types, implying that Ethiopia may serve as a breeding ground for novel STs. Recombination can produce novel STs that cause capsular switching. This has the potential to influence how immunization campaigns affect the burden of invasive pneumococcal illness. The findings highlight the importance of continuous genetic surveillance of the pneumococcal population as a vital step toward enhancing future vaccine design.

• Golparian, Daniel; Cole, Michelle J; Sánchez-Busó, Leonor; Day, Michaela; Jacobsson, Susanne & Uthayakumaran, Thinushaa [Show all 18 contributors for this article] (2024). Antimicrobial-resistant Neisseria gonorrhoeae in Europe in 2020 compared with in 2013 and 2018: a retrospective genomic surveillance study. Lancet Microbe. 5(5), p. e478–e488. doi: 10.1016/S2666-5247(23)00370-1. Full text in Research Archive
• Al-Abri, Seif S.; Abuhasan, Musallam Yunus; Albayat, Soha Shawqi A.; Bai, Xilian; Bastaki, Hamad & Borrow, Ray [Show all 23 contributors for this article] (2023). Meningococcal disease in the Middle East: A report from the Global Meningococcal Initiative. Journal of Infection. ISSN 0163-4453. 88(2), p. 71–76. doi: 10.1016/j.jinf.2023.10.011. Full text in Research Archive
• Watle, Sara Viksmoen; Børud, Bente; Laake, Ida; Baranowska-Hustad, Marta Natalia; Bryant-Bratlie, Diane Lynn & Bekkevold, Terese [Show all 9 contributors for this article] (2023). Antibodies against Neisseria meningitidis serogroups A, C, W and Y in serum and saliva of Norwegian adolescents. Vaccine. ISSN 0264-410X. 41(44), p. 6529–6537. doi: 10.1016/j.vaccine.2023.08.052. Full text in Research Archive Show summary

  Introduction The incidence of invasive meningococcal disease (IMD) among Norwegian 16–19-year-olds was 1–7/100,000 in the decade before the COVID-19 pandemic, with serogroup Y (MenY) dominance. In contrast to many other European countries, meningococcal vaccines are not part of the national immunisation program (NIP) in Norway. This cross-sectional study aimed to measure the degree of natural immunity against Neisseria meningitidis among adolescents in Norway to evaluate the need for introducing tetravalent meningococcal conjugate vaccine (MCV4) in the NIP. Materials and methods Serum and saliva samples were collected from students in upper and lower secondary schools in Norway in 2018. Samples were analysed for meningococcal capsular polysaccharide (PS)-specific antibodies using a bead-based multiplex immunoassay. PS-specific antibody levels were linked to data on meningococcal carriage, vaccination status and risk factors for carriage (assessed with questionnaire) and analysed by linear regression of log transformed concentrations. A subset of samples from unvaccinated individuals was analysed for serum bactericidal antibodies (SBA). Results A total of 1344 participants, median age 16 years (range 12–24), were included in the study. Overall, 60.9% of the participants were female and 1137 (84.6%) were not vaccinated with MCV4. PS-specific antibody concentrations in serum and saliva were low among unvaccinated individuals for all serogroups and only 6.7–20.0% of the subpopulation with high PS-specific antibodies assessed with SBA had protective levels. Unvaccinated MenY carriers had higher levels of MenY anti-PS IgG in serum and IgA in saliva than those not carrying MenY. Use of Swedish snus was associated with lower anti-PS IgG levels in serum and waterpipe use with lower anti-PS IgG levels in saliva. Conclusion Unvaccinated adolescents in Norway have a low degree of natural immunity against the serogroups of N. meningitidis predominating among cases of IMD in this age group. Therefore, introduction of MCV4 for adolescents in the NIP is recommended.

• Orangzeb, Saima; Watle, Sara Viksmoen & Caugant, Dominique A. (2023). Adherence to vaccination guidelines of patients with complete splenectomy in Norway, 2008–2020. Vaccine. ISSN 0264-410X. 41(31), p. 4759–4585. doi: 10.1016/j.vaccine.2023.06.034. Full text in Research Archive Show summary

  The spleen is responsible for blood filtration and mounting an immune response against pathogens. In some people the spleen must be surgically removed because of traumatic events or oncological and hematological conditions. These patients are at higher risk of developing diseases caused by encapsulated bacteria throughout their lives. Thus, immunisations are advised for splenectomised persons to prevent infection caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b (Hib). This study assessed vaccination coverage (VC) among Norwegian patients with surgical asplenia. Using the Nomesco Classification of Surgical Procedures codes, patient information (age, sex, date of initial diagnosis and date of surgery) was acquired from the Norwegian Patient Registry. The National Immunization Register provided information on vaccination status and data of any subsequent invasive bacterial infections were obtained from the Norwegian Surveillance System for Communicable Diseases. From the total population of Norway, 3155 patients who had undergone complete splenectomy were identified. Of these, 914 (29.0%) had received at least one dose of pneumococcal conjugate vaccine (PCV), 1324 (42.0%) at least one dose of pneumococcal polysaccharide vaccine and 589 (18.7%) had received both. Only 4.2% of the patients had received two doses of a meningococcal ACWY conjugate vaccine, while 8.0% of 1467 patients splenectomised after 2014 had received at least two doses of a serogroup B meningococcal vaccine. The VC for Hib was 18.7%. Nearly all splenectomised children under the age of 10 were vaccinated with Hib and PCV as these vaccines are included in the childhood immunisation program. For all vaccines, VC decreased with age. Twenty-nine invasive bacterial infections were registered post-splenectomy in 25 patients. Vaccination according to national recommendations could have prevented at least 8 (28%) of these infections. Our study showed that efforts are required to increase VC of splenectomised individuals in Norway.

• Llorente, Ignacio Garcia; Lee, Yunsung; Brynildsrud, Ola Brønstad; Eldholm, Vegard; Magnus, Per Minor & Blomfeldt, Anita [Show all 10 contributors for this article] (2023). Tracing the adaptive evolution of SARS-CoV-2 during vaccine roll-out in Norway. Virus Evolution. 10(1). doi: 10.1093/ve/vead081. Full text in Research Archive
• Brynildsrud, Ola Brønstad; Watle, Sara Sofie Viksmoen; Alfsnes, Kristian & Caugant, Dominique A. (2023). Invasive meningococcal disease in Norway in the two decades before the COVID-19 pandemic. International Journal of Infectious Diseases. ISSN 1201-9712. 131, p. 130–139. doi: 10.1016/j.ijid.2023.04.005. Full text in Research Archive Show summary

  Objectives Disease caused by the bacterium Neisseria meningitidis remains a worldwide public health challenge, despite the steadily decreasing incidence in Western countries. The objective of this study was to explore the epidemiology of invasive meningococcal disease in Norway over the last two decades. Design All isolates sent to the National Reference Laboratory from patients with invasive meningococcal disease between the years 2000 and 2019 were analyzed using whole genome sequencing (total: 625). Results A five-fold decrease in case numbers occurred over this period, and the situation has gone from being dominated by serogroup B to one where serogroups Y and W are more prevalent. Concurrently, the mean age at infection has increased from 18 to 33 years. Among the 350 serogroup B isolates, 87% were an exact match or cross-reactive with one or both the currently available serogroup B vaccines, but the proportion decreased in the past decade. Core genome analyses revealed a high variation in the number of allelic differences accumulated in epidemiologically linked isolates to the point that near-identical isolates were found several years apart. Conclusion Allelic distance is an imprecise metric for the degree of epidemiologic linkage between isolates in N. meningitidis.

• Osnes, Magnus Nygård; Brynildsrud, Ola Brønstad; Alfsnes, Kristian; Dorp, Lucy van; McKeand, Samantha A & Ross, Jonathan [Show all 17 contributors for this article] (2023). The inter-continental population dynamics of Neisseria gonorrhoeae. eLIFE. doi: 10.7554/eLife.90062.1. Full text in Research Archive
• Næss, Lisbeth Meyer; Maugesten, Ingunn S.; Caugant, Dominique Andree Yvette; Kassu, Afework; Aseffa, Abraham & Børud, Bente (2023). Genetic, Functional, and Immunogenic Analyses of the O-Linked Protein Glycosylation System in Neisseria meningitidis Serogroup A ST-7 Isolates. Journal of Bacteriology. ISSN 0021-9193. 205(3). doi: 10.1128/jb.00458-22. Full text in Research Archive
• Vollan, Hilde Synnøve; Caugant, Dominique Andree Yvette; Eldholm, Vegard; Alfsnes, Kristian; Debech, Nadia & Brynildsrud, Ola Brønstad (2022). Naturally occurring Neisseria gonorrhoeae can have large deletions in housekeeping gene abcZ, making them untypable with multilocus sequence typing. Microbial Genomics. 8(9). doi: 10.1099/mgen.0.000889. Full text in Research Archive Show summary

  The abcZ gene is an essential housekeeping gene in all the Neisseria species. It is one of the seven genes used for multilocus sequence typing (MLST) this genus. It encodes the cytosolic component of an ATP-binding cassette (ABC) transporter complex of unknown function. We report here the finding of a strain of Neisseria gonorrhoeae with a 485 base pair deletion in the 5′ region of the abcZ gene that truncates the protein product from 636 amino acids to 89 amino acids. A second open reading frame (ORF), encoding the latter 388 amino acids of the abcZ gene, was predicted downstream. The deletion will affect MLST profiling; interrogation of genomic sequences from PubMLST revealed that this isolate is not an anomaly. Deletions in abcZ were identified in 256 Neisseria genomes, roughly 0.6% of isolates. Furthermore, these deletions could leave the abcZ gene in a pseudogenized state. Our strain, isolated from a patient with symptoms of gonorrheal infection, nevertheless behaved normal in terms of growth and in vitro phenotypic properties.

• Asturias, Edwin J.; Bai, Xilian; Bettinger, Julie A.; Borrow, Ray; Castillo, Delia Nais & Caugant, Dominique Andree Yvette [Show all 30 contributors for this article] (2022). Meningococcal disease in North America: Updates from the Global Meningococcal Initiative. Journal of Infection. ISSN 0163-4453. 85(6), p. 611–622. doi: 10.1016/j.jinf.2022.10.022. Full text in Research Archive
• MacAlasdair, Neil; Pesonen, Maiju; Brynildsrud, Ola Brønstad; Eldholm, Vegard; Kristiansen, Paul Arne & Corander, Jukka [Show all 8 contributors for this article] (2021). The effect of recombination on the evolution of a population of Neisseria meningitidis. Genome Research. ISSN 1088-9051. 31(7), p. 1258–1268. doi: 10.1101/gr.264465.120. Full text in Research Archive Show summary

  Neisseria meningitidis (the meningococcus) is a major human pathogen with a history of high invasive disease burden, particularly in sub-Saharan Africa. Our current understanding of the evolution of meningococcal genomes is limited by the rarity of large-scale genomic population studies and lack of in-depth investigation of the genomic events associated with routine pathogen transmission. Here, we fill this knowledge gap by a detailed analysis of 2839 meningococcal genomes obtained through a carriage study of over 50,000 samples collected systematically in Burkina Faso, West Africa, before, during, and after the serogroup A vaccine rollout, 2009–2012. Our findings indicate that the meningococcal genome is highly dynamic, with highly recombinant loci and frequent gene sharing across deeply separated lineages in a structured population. Furthermore, our findings illustrate how population structure can correlate with genome flexibility, as some lineages in Burkina Faso are orders of magnitude more recombinant than others. We also examine the effect of selection on the population, in particular how it is correlated with recombination. We find that recombination principally acts to prevent the accumulation of deleterious mutations, although we do also find an example of recombination acting to speed the adaptation of a gene. In general, we show the importance of recombination in the evolution of a geographically expansive population with deep population structure in a short timescale. This has important consequences for our ability to both foresee the outcomes of vaccination programs and, using surveillance data, predict when lineages of the meningococcus are likely to become a public health concern.

• Osnes, Magnus Nygård; Alfsnes, Kristian; Bråte, Jon; Llorente, Ignacio Garcia; Riis, Rasmus Kopperud & Instefjord, Kamilla Heddeland [Show all 16 contributors for this article] (2021). The impact of global lineage dynamics, border restrictions, and emergence of the B.1.1.7 lineage on the SARS-CoV-2 epidemic in Norway. Virus Evolution. 7(2), p. 1–7. doi: 10.1093/ve/veab086. Full text in Research Archive Show summary

  Abstract As the COVID-19 pandemic swept through an immunologically naïve human population, academics and public health professionals scrambled to establish methods and platforms for genomic surveillance and data sharing. This offered a rare opportunity to study the ecology and evolution of SARS-CoV-2 over the course of the ongoing pandemic. Here, we use population genetic and phylogenetic methodology to characterize the population dynamics of SARS-CoV-2 and reconstruct patterns of virus introductions and local transmission in Norway against this backdrop. The analyses demonstrated that the epidemic in Norway was largely import driven and characterized by the repeated introduction, establishment, and suppression of new transmission lineages. This pattern changed with the arrival of the B.1.1.7 lineage, which was able to establish a stable presence concomitant with the imposition of severe border restrictions.

• Alderson, Mark R.; Arkwright, Peter D.; Bai, Xilian; Black, Steve; Borrow, Ray & Caugant, Dominique Andree Yvette [Show all 17 contributors for this article] (2021). Surveillance and control of meningococcal disease in the COVID-19 era: A Global Meningococcal Initiative review. Journal of Infection. ISSN 0163-4453. 84(3), p. 289–296. doi: 10.1016/j.jinf.2021.11.016. Full text in Research Archive
• Watle, Sara Sofie Viksmoen; Næss, Lisbeth Meyer; Tunheim, Gro; Caugant, Dominique A & Wisløff, Torbjørn (2021). Cost-effectiveness of meningococcal vaccination of Norwegian teenagers with a quadrivalent ACWY conjugate vaccine. Human Vaccines & Immunotherapeutics. ISSN 2164-5515. 17(8), p. 2777–2787. doi: 10.1080/21645515.2021.1880209. Full text in Research Archive Show summary

  In Norway, the incidence of invasive meningococcal disease (IMD) is higher among 16–19-year-olds than in the general population. Most IMD cases among teenagers are caused by serogroup Y. Since 2011, one dose of meningococcal ACWY conjugate vaccine (MCV4) has been recommended for teenagers with out- of-pocket payment. The teenagers are usually vaccinated through the school health service at age 18. This study aimed to estimate costs and health gains of introducing MCV4 to Norwegian teenagers through the national immunization program (NIP). A Markov model was used to analyze the cost-effectiveness of universal MCV4 vaccination of either 15-year-olds or 18-years-olds. Occurrences of IMD were simulated from 15 until 23 years of age. Costs were estimated from a healthcare perspective. Sensitivity analyses evaluated the impact of vaccine price, vaccination uptake, IMD incidence and discount rate. Compared to today’s practice of vaccinating 18-year-olds with out-of-pocket payment, introducing MCV4 to 15-year- olds in a NIP-setting, with 90% vaccine uptake and 50% rebate on vaccine price, prevented 3.2 hospita-lizations, 0.20 sequelae and 0.47 deaths among 15–23-year-olds, annually. Total costs were reduced by €30,000 and 9.7 quality-adjusted life-years (QALYs) were gained per birth cohort. The probability of cost- effectiveness was 99.0%, assuming a willingness-to-pay threshold of €86,000/QALY for severe diseases in Norway. Cost-effectiveness was highly dependent on vaccine price. Vaccination of 18-year-olds in a NIP- setting was also cost-effective, but less than NIP-vaccination of 15-year-olds. Introduction of MCV4 to the 15-year-olds in the Norwegian NIP is likely to be cost-effective given a rebate on the vaccine price.

• Sharma, Supriya; Acharya, Jyoti; Caugant, Dominique A; Banjara, Megha Raj; Ghimire, Prakash & Singh, Anjana (2021). Detection of Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae in Culture Negative Cerebrospinal Fluid Samples from Meningitis Patients Using a Multiplex Polymerase Chain Reaction in Nepal. Infectious Disease Reports. ISSN 2036-7430. 13(1), p. 173–180. doi: 10.3390/IDR13010019. Full text in Research Archive Show summary

  The rapid identification of bacteria causing meningitis is crucial as delays in the treatment increase mortality rate. Though considered as the gold standard for the laboratory diagnosis of bacterial meningitis, culture might give false negative results in a case of patients under antibiotics prior to lumbar puncture. This study aimed to detect Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae by a multiplex polymerase chain reaction (PCR) in culture-negative cerebrospinal fluid samples collected from clinically suspected meningitis cases attending different hospitals in Kathmandu, Nepal from January 2017 to December 2019. S. pneumoniae, N. meningitidis and H. influenzae were detected in 8.59% (33/384) of the specimens by PCR and 7.55% (29/384) of the specimens by culture. Correlation between culture and PCR of the same sample was good (Spearman’s rho correlation coefficient = 0.932). However, the difference in positivity between culture and PCR was statistically not significant (p value > 0.05). In four specimens, culture could not detect any of the targeted bacteria whereas PCR could detect presence of H. influenzae. PCR increases the diagnostic yield for bacterial meningitis. PCR may be considered as an adjunctive test for establishing the cause of infection in culture negative clinically suspected meningitis cases.

• Sharma, Supriya; Acharya, Jyoti; Caugant, Dominique Andree Yvette; Aryal, Shreedhar; Banjara, Megha Raj & Ghimire, Prakash [Show all 7 contributors for this article] (2021). Meningococcal Carriage among Household Contacts of Patients with Invasive Meningococcal Disease in Kathmandu, Nepal: A Longitudinal Study. Pathogens. ISSN 2076-0817. 10(7). doi: 10.3390/pathogens10070781. Full text in Research Archive
• Diallo, Kanny; Feteh, Vitalis Fambombi; Ibe, Lilian; Antonio, Martin; Caugant, Dominique Andree Yvette & Plessis, Mignon du [Show all 17 contributors for this article] (2021). Molecular diagnostic assays for the detection of common bacterial meningitis pathogens: A narrative review. EBioMedicine. 65. doi: 10.1016/j.ebiom.2021.103274. Full text in Research Archive Show summary

  Bacterial meningitis is a major global cause of morbidity and mortality. Rapid identification of the aetiologicalagent of meningitis is essential for clinical and public health management and disease prevention given thewide range of pathogens that cause the clinical syndrome and the availability of vaccines that protect againstsome, but not all, of these. Since microbiological culture is complex, slow, and often impacted by prior anti-microbial treatment of the patient, molecular diagnostic assays have been developed for bacterial detection.Distinguishing between meningitis caused byNeisseria meningitidis(meningococcus),Streptococcus pneumo-niae(pneumococcus),Haemophilus influenzae, andStreptococcus agalactiaeand identifying their polysaccha-ride capsules is especially important. Here, we review methods used in the identification of these bacteria,providing an up-to-date account of available assays, allowing clinicians and diagnostic laboratories to makeinformed decisions about which assays to use.

• Aye, Aye Mya Min; Bai, Xilian; Borrow, Ray; Bory, Sotharith; Carlos, Josefina & Caugant, Dominique A [Show all 30 contributors for this article] (2020). Meningococcal disease surveillance in the Asia–Pacific region (2020): The global meningococcal initiative. Journal of Infection. ISSN 0163-4453. 81(5), p. 698–711. doi: 10.1016/j.jinf.2020.07.025. Full text in Research Archive
• Watle, Sara Sofie Viksmoen; Caugant, Dominique A; Tunheim, Gro; Bekkevold, Terese; Laake, Ida & Brynildsrud, Ola Brønstad [Show all 7 contributors for this article] (2020). Meningococcal carriage in Norwegian teenagers: strain characterisation and assessment of risk factors. Epidemiology and Infection. ISSN 0950-2688. 148, p. 1–12. doi: 10.1017/S0950268820000734. Full text in Research Archive Show summary

  Abstract Teenagers have a higher risk of invasive meningococcal disease (IMD) than the general population. This cross-sectional study aimed to characterise strains of Neisseria meningitidis circulating among Norwegian teenagers and to assess risk factors for meningococcal carriage. Oropharyngeal swabs were collected from secondary-school students in southeastern Norway in 2018–2019. Meningococcal isolates were characterised using whole genome sequencing. Risk factors for meningococcal carriage were assessed from questionnaire data. Samples were obtained from 2296 12–24-year-olds (majority 13–19-year-olds). N. meningitidis was identified in 167 (7.3%) individuals. The highest carriage rate was found among 18-year-olds (16.4%). Most carriage isolates were capsule null (40.1%) or genogroup Y (33.5%). Clonal complexes cc23 (35.9%) and cc198 (32.3%) dominated and 38.9% of carriage strains were similar to invasive strains currently causing IMD in Norway. Use of Swedish snus (smokeless tobacco) (OR 1.56, 95% CI 1.07–2.27), kissing >two persons/month (OR 2.76, 95% CI 1.49–5.10) and partying >10 times/3months (OR 3.50, 95% CI 1.45–8.48) were associated with carriage, while age, cigarette smoking, sharing of drinking bottles and meningococcal vaccination were not. The high meningococcal carriage rate among 18-year-olds is probably due to risk-related behaviour. Use of Swedish snus is possibly a new risk factor for meningococcal carriage. Almost 40% of circulating carriage strains have invasive potential.

• Leitmeyer, Katrin; Espinosa, Laura; Broberg, Eeva K.; Struelens, Marc J.; Allerberger, Franz & Dupont, Yves [Show all 42 contributors for this article] (2020). Automated digital reporting of clinical laboratory information to national public health surveillance systems, results of a EU/EEA survey, 2018. Eurosurveillance. ISSN 1025-496X. 25(39). doi: 10.2807/1560-7917.ES.2020.25.39.1900591. Full text in Research Archive
• Osnes, Magnus Nygård; Dorp, Lucy van; Brynildsrud, Ola Brønstad; Alfsnes, Kristian; Schneiders, Thamarai & Templeton, Kate E. [Show all 10 contributors for this article] (2020). Antibiotic treatment regimes as a driver of the global population dynamics of a major gonorrhea lineage. Molecular Biology and Evolution (MBE). ISSN 0737-4038. p. 1–13. doi: 10.1093/molbev/msaa282. Full text in Research Archive
• Musser, James M.; Beres, Stephen B.; Zhu, Luchang; Olsen, Randall J.; Vuopio, Jaana & Hyyryläinen, Hanne-Leena [Show all 16 contributors for this article] (2020). Reduced In Vitro Susceptibility of Streptococcus pyogenes to β-Lactam Antibiotics Associated with Mutations in the pbp2x Gene Is Geographically Widespread. Journal of Clinical Microbiology. ISSN 0095-1137. 58. doi: 10.1128/JCM.01993-19. Full text in Research Archive
• Osnes, Magnus Nygård; Didelot, Xavier; Korne-Elenbaas, Jolinda de; Alfsnes, Kristian; Brynildsrud, Ola Brønstad & Syversen, Gaute [Show all 10 contributors for this article] (2020). Sudden emergence of a Neisseria gonorrhoeae clade with reduced susceptibility to extended-spectrum cephalosporins, Norway. Microbial Genomics. 6(12). doi: 10.1099/mgen.0.000480. Full text in Research Archive Show summary

  Neisseria gonorrhoeae multilocus sequence type (ST)-7827 emerged in a dramatic fashion in Norway in the period 2016–2018. Here, we aim to shed light on the provenance and expansion of this ST. ST-7827 was found to be polyphyletic, but the majority of members belonged to a monophyletic clade we termed PopPUNK cluster 7827 (PC-7827). In Norway, both PC-7827 and ST-7827 isolates were almost exclusively isolated from men. Phylogeographical analyses demonstrated an Asian origin of the genogroup, with multiple inferred exports to Europe and the USA. The genogroup was uniformly resistant to fluoroquinolones, and associated with reduced susceptibility to both azithromycin and the extended-spectrum cephalosporins (ESCs) cefixime and ceftriaxone. From a genetic background including the penA allele 13.001, associated with reduced ESC susceptibility, we identified repeated events of acquisition of porB alleles associated with further reduction in ceftriaxone susceptibility. Transmission of the strain was significantly reduced in Norway in 2019, but our results indicate the existence of a recently established global reservoir. The worrisome drug-resistance profile and rapid emergence of PC-7827 calls for close monitoring of the situation.

• Vorobieva, Veronika; Furberg, Anne-Sofie; Slotved, Hans-Christian; Bazhukova, Tatiana; Haldorsen, Bjørg & Caugant, Dominique A [Show all 9 contributors for this article] (2020). Epidemiological and molecular characterization of Streptococcus pneumoniae carriage strains in pre-school children in Arkhangelsk, northern European Russia, prior to the introduction of conjugate pneumococcal vaccines. BMC Infectious Diseases. 20, p. 1–14. doi: 10.1186/s12879-020-04998-5. Full text in Research Archive Show summary

  Background: The 13-valent Pneumococcal Conjugate Vaccine (PCV-13) was introduced in the National Immunization Programme (NIP) schedule in Russia in March 2014. Previously, the 7-valent Pneumococcal Conjugate Vaccine (PCV-7) was marketed in Russia in 2009 but has never been offered for mass vaccination. A carriage study was performed among children in Arkhangelsk in 2006. The objective was to determine the prevalence of carriage, serotype distribution, antimicrobial susceptibility and the molecular structure of Streptococcus pneumoniae strains before marketing and introduction of PCV-13. Methods: A cross-sectional study was conducted on a cluster-randomized sample of children and a self-administrated questionnaire for parents/guardians. Nasopharyngeal samples were collected from 438 children younger than 7 years attending nurseries and kindergartens in the Arkhangelsk region, Russia. Detailed demographic data, as well as information about the child’s health, traveling, exposure to antimicrobials within the last 3 months and anthropometric measurements were collected for all study subjects. Variables extracted from the questionnaire were analysed using statistic regression models to estimate the risk of carriage. All pneumococcal isolates were examined with susceptibility testing, serotyping and multilocus sequence typing. Results: The overall prevalence of asymptomatic carriage was high and peaking at 36 months with a rate of 57%. PCV-13 covered 67.3% of the detected strains. High rates of non-susceptibility to penicillin, macrolides and multidrug resistance were associated with specific vaccine serotypes, pandemic clones, and local sequence types. Nine percent of isolates represented three globally disseminated disease-associated pandemic clones; penicillin- and macrolide-resistant clones NorwayNT-42 and Poland6B-20, as well as penicillin- and macrolide-susceptible clone Netherlands3-31. A high level of antimicrobial consumption was noted by the study. According to the parent’s reports, 89.5% of the children used at least one antimicrobial regime since birth. None of the hypothesised predictors of S. pneumoniae carriage were statistically significant in univariable and multivariable logistic models. Conclusions: The study identified a high coverage of the PCV-13-vaccine, but serotype replacement and expansion of globally disseminated disease-associated clones with non-vaccine serotypes may be expected. Further surveillance of antimicrobial resistance and serotype distribution is therefore required.

• Willerton, Laura; Lucidarme, Jay; Campbell, Helen; Caugant, Dominique A; Claus, Heike & Jacobsson, Susanne [Show all 12 contributors for this article] (2020). Geographically widespread invasive meningococcal disease caused by a ciprofloxacin resistant non-groupable strain of the ST-175 clonal complex. Journal of Infection. ISSN 0163-4453. 81(4), p. 575–584. doi: 10.1016/j.jinf.2020.08.030. Full text in Research Archive Show summary

  s u m m a r y Introduction: Invasive meningococcal disease (IMD) caused by non-serogroupable (NG) strains mainly affects immunocompromised individuals. Reduced susceptibility to penicillin in meningococci is increasing in Europe but ciprofloxacin resistance remains rare. In 2019, three travel-related meningococcal disease cases caused by a ciprofloxacin-resistant NG strain were identified in England, leading Germany to report four additional IMD cases (2016 to 2019). We describe these and newly identified cases and characterise the strain responsible. Methods: Cases were identified as part of national surveillance and by analysing available genomes using PubMLST tools. Results: Of the cases identified in England in 2019, two geographically distinct cases developed conjunctivitis after returning from Mecca (Kingdom of Saudi Arabia) and a third linked case presented with IMD. Of the four cases from Germany, three occurred in asylum seekers – two familial and a further geographically distinct case. Further IMD cases were identified in Italy (n = 2; 2017–2018), Sweden (n = 1; 2016) and England (n = 1; 2015). A single ST-175 clonal complex (cc175) strain with genosubtype P1.22–11,15–25 was responsible. Decreased susceptibility to penicillin was widespread with three ciprofloxacin resistant subclusters. Constituent isolates were potentially covered by subcapsular vaccines. Conclusion: This disease associated NG cc175 strain exhibits resistance to antibiotics commonly used to prevent IMD but is potentially covered by subcapsular (meningococcal B) vaccines. Crown Copyright © 2020 Published by Elsevier Ltd on behalf of The British Infection Association. This is an open access article under the Open Government License (OGL) (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

• Alfsnes, Kristian; Eldholm, Vegard; Olsen, Anne Olaug; Brynildsrud, Ola Brønstad; Bohlin, Jon & Steinbakk, Martin [Show all 7 contributors for this article] (2020). Genomic epidemiology and population structure of Neisseria gonorrhoeae in Norway, 2016–2017. Microbial Genomics. 6(4). doi: 10.1099/mgen.0.000359. Full text in Research Archive Show summary

  This study presents the nationwide epidemiology of Neisseria gonorrhoeae , using whole-genome sequencing of all culture-positive cases, which comprise roughly 40 % of all cases of gonorrhea reported in Norway from 2016 to 2017. Isolates were assigned to sequence types and Bayesian analysis clusters and variation in genes coding for antibiotic resistance was linked to phenotypic resistance data. The study also included isolates taken from the same patients from different anatomical sites at one or more time points. Comparing these isolates allows for observation of patterns of infections, i.e. multiple reinfections of genetically related clones vs. reinfections of genetically distant clones, and quantification of the genomic variation of closely related isolates from samples taken from a patient within the same day. Demographically, the patients in the study could be split into two groups; one group of patients from the capital with a high proportion of men who have sex with men (MSM), and another consisting of young adults with transmission primarily between males and females from outside the capital. Some clusters of N. gonorrhoeae were restricted to one of these two demographic groups. Pairwise comparison of multiple isolates from the same patients revealed that most were reinfected with different clones. Observations of frequent reinfections in patients is a concern and should be taken into account in the development of improved information and treatment guidelines.

• Feagins, Alicia R.; Ronveaux, Olivier; Taha, Muhamed-Kheir; Caugant, Dominique A; Smith, Vinny & Fernandez, Katya [Show all 9 contributors for this article] (2020). Next generation rapid diagnostic tests for meningitis diagnosis. Journal of Infection. ISSN 0163-4453. 81(5), p. 712–718. doi: 10.1016/j.jinf.2020.08.049. Full text in Research Archive Show summary

  Rapid diagnostic tests (RDTs) are increasingly recognized as valuable, transformative tools for the diagnosis of infectious diseases. Although there are a variety of meningitis RDTs currently available, certain product features restrict their use to specific levels of care and settings. For this reason, the development of meningitis RDTs for use at all levels of care, including those in low-resource settings, was included in the “Defeating Meningitis by 2030” roadmap. Here we address the limitations of available meningitis RDTs and present test options and specifications to consider when developing the next generation of meningitis RDTs.

• Rodgers, Elizabeth; Bentley, Stephen D.; Borrow, Ray; Bratcher, Holly B.; Brisse, Sylvain & Brueggemann, Angela B. [Show all 35 contributors for this article] (2020). The global meningitis genome partnership. Journal of Infection. ISSN 0163-4453. 81(4), p. 510–520. doi: 10.1016/j.jinf.2020.06.064. Full text in Research Archive
• Siira, Lotta Linnea; Vestrheim, Didrik Frimann; Winje, Brita Askeland; Caugant, Dominique & Steens, Anneke (2020). Antimicrobial susceptibility and clonality of Streptococcus pneumoniae isolates recovered from invasive disease cases during a period with changes in pneumococcal childhood vaccination, Norway, 2004–2016. Vaccine. ISSN 0264-410X. 38(34), p. 5454–5463. doi: 10.1016/j.vaccine.2020.06.040. Full text in Research Archive Show summary

  Changes in pneumococcal antimicrobial resistance (AMR) have been reported following use of pneumococcal conjugate vaccines (PCVs) in childhood vaccination programmes. We describe AMR trends and clonality in Norway during 2004–2016; we studied 10,239 invasive pneumococcal disease (IPD) isolates in terms of serotypes, antimicrobial susceptibility, and for a systematically collected subset of 2473 isolates, multilocus sequence types (ST). The IPD cases were notified to the Norwegian Surveillance System for Communicable Diseases and pneumococcal isolates were collected through the National Reference Laboratory for Pneumococci. The cases are sourced from the entire Norwegian population. We supplemented the IPD isolates with isolates from carriage studies in children attending day-care, performed in 2006 (before mass childhood vaccination with PCV7), 2008 (2 years after PCV7 introduction), 2013 (2 years after the transition to PCV13), and 2015. IPD cases were 0–102 years old; median 64 years. Carriage study participants were typically aged 1–5 years. Overall, AMR was low; a maximum of 7% of IPD isolates were resistant, depending on the antimicrobial. Erythromycin and trimethoprim/sulfamethoxazole resistant IPD (ERY-R and SXT-R, respectively) decreased in the PCV7 period (2006–2010). In the PCV13 period (2011–2016) however, we saw an indication of increased non-susceptibility among IPD isolates. This increase was mainly due to non-vaccine serotypes 15A-ST63 (multidrug resistant), 24F-ST162 (SXT-R), 23B-ST2372 (penicillin non-susceptible and SXT-R) and 33F (ERY-R and clindamycin resistant). Resistant or non-susceptible IPD isolates were often clones introduced into Norway during the study period. The exception was ERY-R isolates; initially, these largely consisted of an established serotype 14-ST9 clone, which disappeared after introducing PCV7. The carriage study results mostly resembled the changes seen in IPD with a maximum of 9% of the participants per study carrying resistant pneumococci. As actual PCVs are not fully limiting AMR, higher-valency vaccines and prudent use of antimicrobials are still needed to temper pneumococcal AMR.

• Caugant, Dominique A & Brynildsrud, Ola Brønstad (2019). Neisseria meningitidis: using genomics to understand diversity, evolution and pathogenesis. Nature Reviews Microbiology. ISSN 1740-1526. 18, p. 84–96. doi: 10.1038/s41579-019-0282-6. Full text in Research Archive
• Mihret, Wude; Brusletto, Berit Sletbakk; Øvstebø, Reidun; Siebke, Anne-Marie; Norheim, Gunnstein & Merid, Yared [Show all 15 contributors for this article] (2019). Molecular studies of meningococcal and pneumococcal meningitis patients in Ethiopia. Innate Immunity. ISSN 1753-4259. 25(3), p. 158–167. doi: 10.1177/1753425918806363. Full text in Research Archive Show summary

  Neisseria meningitidis infections in sub-Saharan Africa usually present with distinct symptoms of meningitis but very rarely as fulminant septicemia when reaching hospitals. In Europe, development of persistent meningococcal shock and multiple organ failure occurs in up to 30% of patients and is associated with a bacterial load of >106/ml plasma or serum. We have prospectively studied 27 Ethiopian patients with meningococcal infection as diagnosed and quantified with real-time PCR in the cerebrospinal fluid (CSF) and serum. All presented with symptoms of meningitis and none with fulminant septicemia. The median N. meningitidis copy number (NmDNA) in serum was < 3.5 × 103/ml, never exceeded 1.8 × 105/ml, and was always 10–1000 times higher in CSF than in serum. The levels of LPS in CSF as determined by the limulus amebocyte lysate assay were positively correlated to NmDNA copy number (r = 0.45, P = 0.030), levels of IL-1 receptor antagonist, (r = 0.46, P = 0.017), and matrix metallopeptidase-9 (MMP-9; r = 0.009). We also compared the inflammatory profiles of 19 mediators in CSF of the 26 meningococcal patients (2 died and 2 had immediate severe sequelae) with 16 patients with Streptococcus pneumoniae meningitis (3 died and 3 with immediate severe sequelae). Of 19 inflammatory mediators tested, 9 were significantly higher in patients with pneumococcal meningitis and possibly linked to worse outcome.

• Bai, Xilian; Borrow, Ray; Bukovski, Suzana; Caugant, Dominique A; Culic, Davor & Delic, Snezana [Show all 23 contributors for this article] (2019). Prevention and control of meningococcal disease: Updates from the Global Meningococcal Initiative in Eastern Europe. Journal of Infection. ISSN 0163-4453. 79(6), p. 528–541. doi: 10.1016/j.jinf.2019.10.018. Full text in Research Archive
• Sharma, Supriya; Acharya, Jyoti; Caugant, Dominique A; Thapa, Jeewan; Bajracharya, Manju & Kayastha, Madhusudan [Show all 12 contributors for this article] (2019). Meningococcal Meningitis: A Multicentric Hospital-based Study in Kathmandu, Nepal. Open Microbiology Journal. 13, p. 273–278. doi: 10.2174/1874285801913010273. Full text in Research Archive
• Brynildsrud, Ola Brønstad; Eldholm, Vegard; Rakhimova, Adilya; Kristiansen, Paul Arne & Caugant, Dominique A (2019). Gauging the epidemic potential of a widely circulating non-invasive meningococcal strain in Africa. Microbial Genomics. 5(8). doi: 10.1099/mgen.0.000290. Full text in Research Archive Show summary

  Neisseria meningitidis colonizes the human oropharynx and transmits mainly via asymptomatic carriage. Actual outbreaks of meningococcal meningitis are comparatively rare and occur when susceptible populations are exposed to hypervirulent clones, genetically distinct from the main carriage isolates. However, carriage isolates can evolve into pathogens through a limited number of recombination events. The present study examines the potential for the sequence type (ST)-192, by far the dominant clone recovered in recent meningococcal carriage studies in sub-Saharan Africa, to evolve into a pathogen. We used whole-genome sequencing on a collection of 478 meningococcal isolates sampled from 1- to 29- year-old healthy individuals in Arba Minch, southern Ethiopia in 2014. The ST-192 clone was identified in nearly 60 % of the carriers. Using complementary short- and long-read techniques for whole-genome sequencing, we were able to completely resolve genomes and thereby identify genomic differences between the ST-192 carriage strain and known pathogenic clones with the highest possible resolution. We conclude that it is possible, but unlikely, that ST-192 could evolve into a significant pathogen, thus, becoming the major invasive meningococcus clone in the meningitis belt of Africa following upcoming mass vaccination with a polyvalent conjugate vaccine that targets the A, C, W, Y and X capsules.

• Topaz, Nadav; Caugant, Dominique A; Taha, Muhamed-Kheir; Brynildsrud, Ola Brønstad; Debech, Nadia & Hong, Eva [Show all 14 contributors for this article] (2019). Phylogenetic relationships and regional spread of meningococcal strains in the meningitis belt, 2011–2016. EBioMedicine. 41, p. 488–496. doi: 10.1016/j.ebiom.2019.02.054. Full text in Research Archive Show summary

  Background Historically, the major cause of meningococcal epidemics in the meningitis belt of sub-Saharan Africa has been Neisseria meningitidis serogroup A (NmA), but the incidence has been substantially reduced since the introduction of a serogroup A conjugate vaccine starting in 2010. We performed whole-genome sequencing on isolates collected post-2010 to assess their phylogenetic relationships and inter-country transmission. Methods A total of 716 invasive meningococcal isolates collected between 2011 and 2016 from 11 meningitis belt countries were whole-genome sequenced for molecular characterization by the three WHO Collaborating Centers for Meningitis. Findings We identified three previously-reported clonal complexes (CC): CC11 (n = 434), CC181 (n = 62) and CC5 (n = 90) primarily associated with NmW, NmX, and NmA, respectively, and an emerging CC10217 (n = 126) associated with NmC. CC11 expanded throughout the meningitis belt independent of the 2000 Hajj outbreak strain, with isolates from Central African countries forming a distinct sub-lineage within this expansion. Two major sub-lineages were identified for CC181 isolates, one mainly expanding in West African countries and the other found in Chad. CC10217 isolates from the large outbreaks in Nigeria and Niger were more closely related than those from the few cases in Mali and Burkina Faso. Interpretations Whole-genome based phylogenies revealed geographically distinct strain circulation as well as inter-country transmission events. Our results stress the importance of continued meningococcal molecular surveillance in the region, as well as the development of an affordable vaccine targeting these strains.

• Greenwood, Brian M.; Aseffa, Abraham; Caugant, Dominique A; Diallo, Kanny; Kristiansen, Paul Arne & Maiden, Martin C.J. [Show all 8 contributors for this article] (2019). Narrative review of methods and findings of recent studies on the carriage of meningococci and other Neisseria species in the African Meningitis Belt. Tropical medicine & international health. ISSN 1360-2276. 24(2), p. 143–154. doi: 10.1111/tmi.13185. Full text in Research Archive
• Krone, Manuel; Gray, Steve; Abad, Raquel; Skoczyńska, Anna; Stefanelli, Paola & Ende, Arie van der [Show all 22 contributors for this article] (2019). Increase of invasive meningococcal serogroup W disease in Europe, 2013 to 2017. Eurosurveillance. ISSN 1025-496X. 24(14). doi: 10.2807/1560-7917.ES.2019.24.14.1800245. Full text in Research Archive
• Kachroo, Priyanka; Eraso, Jesus M.; Beres, Stephen B.; Olsen, Randall J.; Zhu, Luchang & Nasser, Waleed [Show all 31 contributors for this article] (2019). Integrated analysis of population genomics, transcriptomics and virulence provides novel insights into Streptococcus pyogenes pathogenesis. Nature Genetics. ISSN 1061-4036. 51(3), p. 548–559. doi: 10.1038/s41588-018-0343-1. Full text in Research Archive
• Muzzi, Alessandro; Brozzi, Alessandro; Serino, Laura; Bodini, Margherita; Abad, Raquel & Caugant, Dominique A [Show all 27 contributors for this article] (2019). Genetic Meningococcal Antigen Typing System (gMATS): A genotyping tool that predicts 4CMenB strain coverage worldwide. Vaccine. ISSN 0264-410X. 37(7), p. 991–1000. doi: 10.1016/j.vaccine.2018.12.061. Full text in Research Archive
• Avecedo, Reinaldo; Bai, Xilian; Borrow, Ray; Caugant, Dominique A; Carlos, Josefina & Ceyhan, Mehmet [Show all 27 contributors for this article] (2018). The Global Meningococcal Initiative meeting on prevention of meningococcal disease worldwide: epidemiology, surveillance, hypervirulent strains, antibiotic resistance and high-risk populations. Expert Review of Vaccines. ISSN 1476-0584. 18(1), p. 15–30. doi: 10.1080/14760584.2019.1557520. Full text in Research Archive
• Bårnes, Guro Kristine; Gudina, Esayas Kebede; Berhane, Melkamu; Abdissa, Alemseged; Tesfaw, Getnet & Abebe, Gemeda [Show all 9 contributors for this article] (2018). New molecular tools for meningitis diagnostics in Ethiopia – a necessary step towards improving antimicrobial prescription. BMC Infectious Diseases. 18(1). doi: 10.1186/s12879-018-3589-4. Full text in Research Archive Show summary

  Background Meningitis remains a top cause of premature death and loss of disability-adjusted life years in low-income countries. In resource-limited settings, proper laboratory diagnostics are often scarce and knowledge about national and local epidemiology is limited. Misdiagnosis, incorrect treatment and overuse of antibiotics are potential consequences, especially for viral meningitis. Methods A prospective study was conducted over three months in a teaching hospital in Ethiopia with limited laboratory resources. Cerebrospinal fluid (CSF) samples from patients with suspected meningitis were analysed using a multiplex PCR-based system (FilmArray, BioFire), in addition to basic routine testing with microscopy and culture. Clinical data, as well as information on treatment and outcome were collected. Results Two hundred and eighteen patients were included; 117 (54%) neonates (0–29 days), 63 (29%) paediatrics (1 month-15 years) and 38 (17%) adults (≥16 years). Of 218 CSF samples, 21 (10%) were PCR positive; 4% in neonates, 14% in paediatrics and 18% in adults. Virus was detected in 57% of the PCR positive samples, bacteria in 33% and fungi in 10%. All CSF samples that were PCR positive for a bacterial agent had a white cell count ≥75 cells/mm3 and/or turbid appearance. The majority (90%) of patients received more than one antibiotic for treatment of the meningitis episode. There was no difference in the mean number of different antibiotics received or in the cumulative number of days with antibiotic treatment between patients with a microorganism detected in CSF and those without. Conclusions A rapid molecular diagnostic system was successfully implemented in an Ethiopian setting without previous experience of molecular diagnostics. Viral meningitis was diagnosed for the first time in routine clinical practice in Ethiopia, and viral agents were the most commonly detected microorganisms in CSF. This study illustrates the potential of rapid diagnostic tests for reducing antibiotic usage in suspected meningitis cases. However, the cost of consumables for the molecular diagnostic system used in this study limits its use in low-income countries.

• Bratcher, Holly B.; Brehony, Carina; Heuberger, Sigrid; Pieridou-Bagatzouni, Despo; Křížová, Pavla & Hoffmann, Steen [Show all 19 contributors for this article] (2018). Establishment of the european meningococcal strain collection genome library (EMSC-GL) for the 2011 to 2012 epidemiological year. Eurosurveillance. ISSN 1025-496X. 23(20). doi: 10.2807/1560-7917.ES.2018.23.20.17-00474. Full text in Research Archive
• Børud, Bente; Bårnes, Guro Kristine; Brynildsrud, Ola Brønstad; Fritzsønn, Elisabeth & Caugant, Dominique A (2018). Genotypic and phenotypic characterization of the O-linked protein glycosylation system reveals high glycan diversity in paired meningococcal carriage isolates. Journal of Bacteriology. ISSN 0021-9193. 200(16). doi: 10.1128/JB.00794-17. Full text in Research Archive
• Brynhildsrud, Ola Brønstad; Eldholm, Vegard; Bohlin, Jon; Uadiale, Kennedy; Obaro, Stephen & Caugant, Dominique A (2018). Acquisition of virulence genes by a carrier strain gave rise to the ongoing epidemics of meningococcal disease in West Africa. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 115(21), p. 5510–5515. doi: 10.1073/pnas.1802298115. Full text in Research Archive Show summary

  In the African meningitis belt, a region of sub-Saharan Africa comprising 22 countries from Senegal in the west to Ethiopia in the east, large epidemics of serogroup A meningococcal meningitis have occurred periodically. After gradual introduction from 2010 of mass vaccination with a monovalent meningococcal A conjugate vaccine, serogroup A epidemics have been eliminated. Starting in 2013, the northwestern part of Nigeria has been affected by yearly outbreaks of meningitis caused by a novel strain of serogroup C Neisseria meningitidis (NmC). In 2015, the strain spread to the neighboring country Niger, where it caused a severe epidemic. Following a relative calm in 2016, the largest ever recorded epidemic of NmC broke out in Nigeria in 2017. Here, we describe the recent evolution of this new outbreak strain and show how the acquisition of capsule genes and virulence factors by a strain previously circulating asymptomatically in the African population led to the emergence of a virulent pathogen. This study illustrates the power of long-read whole-genome sequencing, combined with Illumina sequencing, for high-resolution epidemiological investigations.

• McNeil, Lisa K.; Donald, Robert G. K.; Gribenko, Alexey; French, Roger; Lambert, Nathaniel & Harris, Shannon L. [Show all 26 contributors for this article] (2018). Predicting the Susceptibility of Meningococcal Serogroup B Isolates to Bactericidal Antibodies Elicited by Bivalent rLP2086, a Novel Prophylactic Vaccine. mBio. ISSN 2161-2129. 9(2). doi: 10.1128/mBio.00036-18. Full text in Research Archive
• Vollan, Hilde Synnøve; Tannæs, Tone Møller; Caugant, Dominique A; Vriend, Gert & Bukholm, Geir (2017). Outer membrane phospholipase A's roles in Helicobacter pylori acid adaptation. Gut Pathogens. 9(1). doi: 10.1186/s13099-017-0184-y. Full text in Research Archive Show summary

  Background The pH of the human gastric mucosa varies around 2.5 so that only bacteria with strong acidic stress tolerance can colonize it. The ulcer causing Helicobacter pylori thrives in the gastric mucosa. We analyse the roles of the key outer membrane protein OMPLA in its roles in acid tolerance. Results The homology model of Helicobacter pylori outer membrane phospholipase A (OMPLA) reveals a twelve stranded β-barrel with a pore that allows molecules to pass with a diameter up to 4 Å. Structure based multiple sequence alignments revealed the functional roles of many amino acids, and led to the suggestion that OMPLA has multiple functions. Besides its role as phospholipase it lets urea enter and ammonium exit the periplasm. Combined with an extensive literature study, our work leads to a comprehensive model for H. pylori’s acid tolerance. This model is based on the conversion of urea into ammonium, and it includes multiple roles for OMPLA and involves two hitherto little studied membrane channels in the OMPLA operon. Conclusion The three-dimensional model of OMPLA predicts a transmembrane pore that can aid H. pylori’s acid tolerance through urea influx and ammonium efflux. After urea passes through OMPLA into the periplasm, it passes through the pH-gated inner membrane channel UreI into the cytoplasm where urease hydrolyses it into NH3 and CO2. Most of the NH3 becomes NH4 + that is likely to need an inner membrane channel to reach the periplasm. Two genes that are co-regulated with OMPLA in gastric Helicobacter operons could aid this transport. The NH4 + that might leave the cell through the OMPLA pore has been implicated in H. pylor’s pathogenesis.

• Borrow, Ray; Caugant, Dominique A; Ceyhan, Mehmet; Christensen, Hannah; Dinleyici, Ener Cagri & Findlow, Jamie [Show all 15 contributors for this article] (2017). Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative. Journal of Infection. ISSN 0163-4453. 75(1), p. 1–11. doi: 10.1016/j.jinf.2017.04.007. Full text in Research Archive
• Page, Anne-Laure; Coldiron, Matthew E.; Gamougam, Kadidja; Acyl, Mahmaat Ali; Tamadji, Mbaihol & Lastrucci, Céline [Show all 11 contributors for this article] (2017). Four years of case-based surveillance of meningitis following the introduction of MenAfriVac in Moissala, Chad: lessons learned. Tropical medicine & international health. ISSN 1360-2276. 22(12), p. 1561–1568. doi: 10.1111/tmi.12987. Full text in Research Archive
• Bårnes, Guro Kristine; Brynildsrud, Ola Brønstad; Børud, Bente; Workalemahu, Bereket; Kristiansen, Paul Arne & Beyene, Demissew Balcha [Show all 8 contributors for this article] (2017). Whole genome sequencing reveals within-host genetic changes in paired meningococcal carriage isolates from Ethiopia. BMC Genomics. 18. doi: 10.1186/s12864-017-3806-3. Full text in Research Archive Show summary

  Background Meningococcal colonization is a prerequisite for transmission and disease, but the bacterium only very infrequently causes disease while asymptomatic carriage is common. Carriage is highly dynamic, showing a great variety across time and space within and across populations, but also within individuals. The understanding of genetic changes in the meningococcus during carriage, when the bacteria resides in its natural niche, is important for understanding not only the carriage state, but the dynamics of the entire meningococcal population. Results Paired meningococcal isolates, obtained from 50 asymptomatic carriers about 2 months apart were analyzed with whole genome sequencing (WGS). Phylogenetic analysis revealed that most paired isolates from the same individual were closely related, and the average and median number of allelic differences between paired isolates defined as the same strain was 35. About twice as many differences were seen between isolates from different individuals within the same sequence type (ST). In 8%, different strains were detected at different time points. A difference in ST was observed in 6%, including an individual who was found to carry three different STs over the course of 9 weeks. One individual carried different strains from the same ST. In total, 566 of 1605 cgMLST genes had undergone within-host genetic changes in one or more pairs. The most frequently changed cgMLST gene was relA that was changed in 47% of pairs. Across the whole genome, pilE, differed mostly, in 85% of the pairs. The most frequent mechanisms of genetic difference between paired isolates were phase variation and recombination, including gene conversion. Different STs showed variation with regard to which genes that were most frequently changed, mostly due to absence/presence of phase variation.

• Diallo, Kanny; Gamougam, Kadija; Daugla, Doumagoum M; Harrison, OB; Bray, James E. & Caugant, Dominique A [Show all 13 contributors for this article] (2017). Hierarchical genomic analysis of carried and invasive serogroup A Neisseria meningitidis during the 2011 epidemic in Chad. BMC Genomics. 18(1). doi: 10.1186/s12864-017-3789-0. Full text in Research Archive
• Mihret, Wude; Lema, Tsehaynesh; Merid, Yared; Kassu, Afework; Abebe, Workeabeba & Moges, Beyene [Show all 20 contributors for this article] (2016). Surveillance of bacterial meningitis, Ethiopia, 2012–2013. Emerging Infectious Diseases. ISSN 1080-6040. 22(1), p. 75–78. doi: 10.3201/eid2201.150432. Full text in Research Archive Show summary

  Ethiopia has the second-largest population (≈94 million in 2013) among the meningitis belt countries of sub-Saharan Africa (1). However, during 2001–2010, a median of only 1,056 suspected meningitis cases per year (range 5–8,571/year) was reported to the World Health Organization (2). The largest meningitis epidemics occurred in 1981 (3) and 1989 (4), resulting in ≈45,000 and ≈50,000 cases, respectively. Serogroup A meningococci were the major cause of these epidemics, although serogroup C strains were also identified in 1981, 1983–84, and during outbreaks in 2000 and 2003 (5). Conjugate vaccines against Haemophilus influenzae serotype b, Streptococcus pneumoniae (pneumococcal conjugate vaccine [PCV] 10), and Neisseria meningitidis serogroup A (MenAfriVac) were introduced in 2007, 2011, and 2013–2015, respectively. Because data permitting assessment of these vaccines are limited, we implemented a surveillance study.

• Bårnes, Guro Kristine; Kristiansen, Paul Arne; Beyene, Demissew; Workalemahu, Bereket; Fissiha, Paulos & Merdekios, Behailu [Show all 10 contributors for this article] (2016). Prevalence and epidemiology of meningococcal carriage in Southern Ethiopia prior to implementation of MenAfriVac, a conjugate vaccine. BMC Infectious Diseases. 16(1). doi: 10.1186/s12879-016-1975-3. Full text in Research Archive Show summary

  Background Neisseria meningitidis colonizes humans and transmits mainly by asymptomatic carriage. We sought to determine the prevalence and epidemiology of meningococcal carriage in Ethiopia prior to the introduction of MenAfriVac, a serogroup A meningococcal conjugate vaccine. Methods A cross-sectional meningococcal carriage study was conducted in Arba Minch, southern Ethiopia. A total of 7479 oropharyngeal samples were collected from 1 to 29 year old volunteers, between March and October, 2014. The swabs were cultured for N. meningitidis and Neisseria lactamica in Ethiopia. N. meningitidis isolates were confirmed and characterized by their serogroup, sequence type (ST) and PorA:FetA profile in Norway. Results Overall carriage prevalence was 6.6 %. There was no significant difference in overall carriage between male (6.7 %) and female (6.4 %) participants. Highest carriage prevalence (10.9 %) for females was found in the 15–19 years of age, while prevalence among males was highest (11.3 %) in the 20–24 age group. Non-groupable isolates dominated (76.4 %), followed by serogroups X (14.0 %) and W (5.9 %) isolates. No serogroup A was found. Most non-groupable isolates were ST-192. Serogroup W isolates were assigned to the ST-11 clonal complex, and serogroup X isolates to the ST-181 and ST-41/44 clonal complexes. Overall carriage prevalence of N. lactamica was 28.1 %. Carriage of N. meningitidis and N. lactamica varied depending on age and geographic area, but there was no association between carriage of the two species. Conclusions Epidemic strains of serogroups W and X were circulating in this area of Ethiopia. As no serogroup A was found among the carriage isolates the immediate impact of mass-vaccination with MenAfriVac on transmission of N. meningitidis in this population is expected to be marginal.

• Uadiale, Kennedy; Bestman, Agatha; Kamau, Charity; Caugant, Dominique A & Greig, Jane (2016). Evaluation of Pastorex meningitis kit performance for the rapid identification of Neisseria meningitidis serogroup C in Nigeria. Transactions of the Royal Society of Tropical Medicine and Hygiene. ISSN 0035-9203. 110(7), p. 381–385. doi: 10.1093/trstmh/trw046. Full text in Research Archive
• Naseer, Mohammed Umaer; Steinbakk, Martin; Blystad, Hans Henrik & Caugant, Dominique A (2016). Epidemiology of invasive group A streptococcal infections in Norway 2010–2014: A retrospective cohort study. European Journal of Clinical Microbiology and Infectious Diseases. ISSN 0934-9723. 35(10), p. 1639–1648. doi: 10.1007/s10096-016-2704-y. Full text in Research Archive
• Bårnes, Guro Kristine; Workalemahu, Bereket; Kristiansen, Paul Arne; Beyene, Demissew Balcha; Merdekios, Behailu & Fissiha, P. [Show all 9 contributors for this article] (2016). Salivary and serum antibody response against Neisseria meningitidis after vaccination with conjugate polysaccharide vaccines in Ethiopian volunteers. Scandinavian Journal of Immunology. ISSN 0300-9475. 84(2), p. 118–129. doi: 10.1111/sji.12451. Full text in Research Archive Show summary

  Meningococcal conjugate vaccines induce serum antibodies crucial for protection against invasive disease. Salivary antibodies are believed to be important for hindering meningococcal acquisition and/or clearance of established carriage. In this study, we measured salivary IgA and IgG antibodies induced by vaccination with a monovalent serogroup A conjugate vaccine or a tetravalent A, C, W and Y conjugate vaccine, in comparison with antibody levels in serum. Saliva and serum samples from Ethiopian volunteers (1–29 years) collected before and eight times on a weekly basis after receiving the serogroup A conjugate vaccine, the tetravalent serogroup A, C, W and Y conjugate vaccine, or no vaccine (control group), were analysed using a multiplex microsphere immunoassay for antibody detection. Serogroup-specific IgG antibody levels in saliva increased significantly after vaccination with both vaccines. The monovalent serogroup A vaccine also induced an increase in salivary IgA antibodies. A strong correlation between serogroup-specific IgG antibodies in saliva and serum, and a somewhat lower correlation for IgA, was observed for all serogroups. There was also a strong correlation between specific secretory IgA and IgA antibodies in saliva for all serogroups. Meningococcal conjugate vaccines are able to elicit salivary antibodies against serogroup A, C, W and Y correlating with antibody levels in serum. The strong correlation between saliva and serum antibody levels indicates that saliva may be used as a surrogate of systemic antibody responses.

• Chow, Jaime; Uadiale, Kennedy; Bestman, Agatha; Kamau, Charity; Caugant, Dominique A & Shehu, Aminu [Show all 7 contributors for this article] (2016). Invasive Meningococcal Meningitis Serogroup C Outbreak in Northwest Nigeria, 2015 - Third Consecutive Outbreak of a New Strain. PLOS Currents. 8(264658). doi: 10.1371/currents.outbreaks.06d10b6b4e690917d8b0a04268906143. Full text in Research Archive
• Borrow, Ray; Alarcon, Pedro; Carlos, Josefina; Caugant, Dominique A; Christensen, Hannah & Debbag, Roberto [Show all 19 contributors for this article] (2016). The Global Meningococcal Initiative: global epidemiology, the impact of vaccines on meningococcal disease and the importance of herd protection. Expert Review of Vaccines. ISSN 1476-0584. 16(4), p. 313–328. doi: 10.1080/14760584.2017.1258308. Full text in Research Archive
• Kretz, Cecilia B.; Retchless, Adam C.; Sidikou, Fati; Issaka, Bassira; Ousmane, Sani & Schwartz, Stephanie [Show all 21 contributors for this article] (2016). Whole-genome characterization of epidemic Neisseria meningitidis serogroup C and resurgence of serogroup W, Niger, 2015. Emerging Infectious Diseases. ISSN 1080-6040. 22(10), p. 1762–1768. doi: 10.3201/eid2210.160468. Full text in Research Archive Show summary

  In 2015, Niger reported the largest epidemic of Neisseria meningitidis serogroup C (NmC) meningitis in sub-Saharan Africa. The NmC epidemic coincided with serogroup W (NmW) cases during the epidemic season, resulting in a total of 9,367 meningococcal cases through June 2015. To clarify the phylogenetic association, genetic evolution, and antibiotic determinants of the meningococcal strains in Niger, we sequenced the genomes of 102 isolates from this epidemic, comprising 81 NmC and 21 NmW isolates. The genomes of 82 isolates were completed, and all 102 were included in the analysis. All NmC isolates had sequence type 10217, which caused the outbreaks in Nigeria during 2013-2014 and for which a clonal complex has not yet been defined. The NmC isolates from Niger were substantially different from other NmC isolates collected globally. All NmW isolates belonged to clonal complex 11 and were closely related to the isolates causing recent outbreaks in Africa.

• Steens, Anneke; Caugant, Dominique A; Aaberge, Ingeborg Sundsvalen & VESTRHEIM, DIDRIK FRIMANN (2015). Decreased carriage and genetic shifts in the Streptococcus pneumoniae population after changing the seven-valent to the thirteen-valent pneumococcal vaccine in Norway. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 34(8), p. 875–883. doi: 10.1097/INF.0000000000000751. Full text in Research Archive
• Bårnes, Guro Kristine; Kristiansen, Paul Arne; Caugant, Dominique A & Næss, Lisbeth Meyer (2015). Development and evaluation of a multiplex microsphere assay for quantification of IgG and IgA antibodies against Neisseria meningitidis serogroup A, C, W and Y polysaccharides. Clinical and Vaccine Immunology. ISSN 1556-6811. 22(7), p. 697–705. doi: 10.1128/CVI.00087-15. Full text in Research Archive
• Kristiansen, Paul Arne; Jørgensen, Hannah Joan & Caugant, Dominique (2015). Serogroup A meningococcal conjugate vaccines in Africa. Expert Review of Vaccines. ISSN 1476-0584. 14(11), p. 1441–1458. doi: 10.1586/14760584.2015.1084232. Full text in Research Archive
• Diomandé, Fabien V.K.; Djingarey, Mamoudou H.; Daugla, Doumagoum M.; Novak, Ryan T.; Kristiansen, Paul Arne & Collard, Jean-Marc [Show all 20 contributors for this article] (2015). Public health impact after the introduction of PsA-TT: The first 4 years. Clinical Infectious Diseases. ISSN 1058-4838. 61, p. S467–S472. doi: 10.1093/cid/civ499. Full text in Research Archive
• Gamougam, Kadidja; Daugla, Doumagoum M.; Toralta, Jacques; Ngadoua, Cyriaque; Fermon, Florence & Page, Anne-Laure [Show all 12 contributors for this article] (2015). Continuing effectiveness of serogroup a meningococcal conjugate Vaccine, Chad, 2013. Emerging Infectious Diseases. ISSN 1080-6040. 21(1), p. 115–118. doi: 10.3201/eid2101.140256. Full text in Research Archive
• Harrison, Odile B; Bray, James E.; Maiden, Martin C.J. & Caugant, Dominique A (2015). Genomic Analysis of the Evolution and Global Spread of Hyper-invasive Meningococcal Lineage 5. EBioMedicine. 2(3), p. 234–243. doi: 10.1016/j.ebiom.2015.01.004. Full text in Research Archive
• Brehony, Carina; Trotter, Caroline L.; Ramsay, Mary E.; Chandra, Manosree; Jolley, Keith A. & Ende, Arie van der [Show all 30 contributors for this article] (2014). Implications of differential age distribution of disease-associated meningococcal lineages for vaccine development. Clinical and Vaccine Immunology. ISSN 1556-6811. 21(6), p. 847–853. doi: 10.1128/CVI.00133-14. Full text in Research Archive
• Daugla, D M; Gami, J P; Gamougam, K; Naibei, N; Mbainadji, L & Narbé, M [Show all 29 contributors for this article] (2014). Effect of a serogroup A meningococcal conjugate vaccine (PsA-TT) on serogroup A meningococcal meningitis and carriage in Chad: a community study. The Lancet. ISSN 0140-6736. 383(9911), p. 40–47. doi: 10.1016/S0140-6736(13)61612-8. Full text in Research Archive
• Koeberling, O; Ispasanie, E; Hauser, Julia; Rossi, Omar; Pluschke, Gerd & Caugant, Dominique [Show all 8 contributors for this article] (2014). A broadly-protective vaccine against meningococcal disease in sub-Saharan Africa based on Generalized Modules for Membrane Antigens (GMMA). Vaccine. ISSN 0264-410X. 32(23), p. 2688–2695. doi: 10.1016/j.vaccine.2014.03.068. Full text in Research Archive
• Holst, Johan; Comanducci, M; Bambini, S; Muzzi, A; Comandi, S & Oksnes, Jan [Show all 10 contributors for this article] (2014). Variability of genes encoding surface proteins used as vaccine antigens in meningococcal endemic and epidemic strain panels from Norway. Vaccine. ISSN 0264-410X. 32(23), p. 2722–2731. doi: 10.1016/j.vaccine.2014.02.068. Full text in Research Archive
• Kristiansen, Paul Arne; Ba, Absatou Ky; Ouédraogo, Abdoul-Salam; Sanou, Idrissa; Ouédraogo, Rasmata & Sangaré, Lassana [Show all 13 contributors for this article] (2014). Persistent low carriage of serogroup A Neisseria meningitidis two years after mass vaccination with the meningococcal conjugate vaccine, MenAfriVac. BMC Infectious Diseases. 14:663. doi: 10.1186/s12879-014-0663-4. Full text in Research Archive Show summary

  Background The conjugate vaccine against serogroup A Neisseria meningitidis (NmA), MenAfriVac, is currently being introduced throughout the African meningitis belt. In repeated multicentre cross-sectional studies in Burkina Faso we demonstrated a significant effect of vaccination on NmA carriage for one year following mass vaccination in 2010. A new multicentre carriage study was performed in October-November 2012, two years after MenAfriVac mass vaccination. Methods Oropharyngeal samples were collected and analysed for presence of N. meningitidis (Nm) from a representative selection of 1-29-year-olds in three districts in Burkina Faso using the same procedures as in previous years. Characterization of Nm isolates included serogrouping, multilocus sequence typing, and porA and fetA sequencing. A small sample of invasive isolates collected during the epidemic season of 2012 through the national surveillance system were also analysed. Results From a total of 4964 oropharyngeal samples, overall meningococcal carriage prevalence was 7.86%. NmA prevalence was 0.02% (1 carrier), significantly lower (OR, 0.05, P = 0.005, 95% CI, 0.006-0.403) than pre-vaccination prevalence (0.39%). The single NmA isolate was sequence type (ST)-7, P1.20,9;F3-1, a clone last identified in Burkina Faso in 2003. Nm serogroup W (NmW) dominated with a carriage prevalence of 6.85%, representing 87.2% of the isolates. Of 161 NmW isolates characterized by molecular techniques, 94% belonged to the ST-11 clonal complex and 6% to the ST-175 complex. Nm serogroup X (NmX) was carried by 0.60% of the participants and ST-181 accounted for 97% of the NmX isolates. Carriage prevalence of serogroup Y and non-groupable Nm was 0.20% and 0.18%, respectively. Among the 20 isolates recovered from meningitis cases, NmW dominated (70%), followed by NmX (25%). ST-2859, the only ST with a serogroup A capsule found in Burkina Faso since 2004, was not found with another capsule, neither among carriage nor invasive isolates. Conclusions The significant reduction of NmA carriage still persisted two years following MenAfriVac vaccination, and no cases of NmA meningitis were recorded. High carriage prevalence of NmW ST-11 was consistent with the many cases of NmW meningitis in the epidemic season of 2012 and the high proportion of NmW ST-11 among the characterized invasive isolates.

• Skaare, Dagfinn; Anthonisen, Inger Lill; Caugant, Dominique A; Jenkins, Andrew; Steinbakk, Martin & Strand, Linda [Show all 9 contributors for this article] (2014). Multilocus sequence typing and ftsI sequencing: A powerful tool for surveillance of penicillin-binding protein 3-mediated beta-lactam resistance in nontypeable Haemophilus influenzae. BMC Microbiology. 14. doi: 10.1186/1471-2180-14-131. Full text in Research Archive Show summary

  Background Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altered penicillin-binding protein 3 (PBP3) is increasing worldwide. Low-level resistant isolates with the N526K substitution (group II low-rPBP3) predominate in most geographical regions, while high-level resistant isolates with the additional S385T substitution (group III high-rPBP3) are common in Japan and South Korea. Knowledge about the molecular epidemiology of rPBP3 strains is limited. We combined multilocus sequence typing (MLST) and ftsI/PBP3 typing to study the emergence and spread of rPBP3 in nontypeable H. influenzae (NTHi) in Norway. Results The prevalence of rPBP3 in a population of 795 eye, ear and respiratory isolates (99% NTHi) from 2007 was 15%. The prevalence of clinical PBP3-mediated resistance to ampicillin was 9%, compared to 2.5% three years earlier. Group II low-rPBP3 predominated (96%), with significant proportions of isolates non-susceptible to cefotaxime (6%) and meropenem (20%). Group III high-rPBP3 was identified for the first time in Northern Europe. Four MLST sequence types (ST) with characteristic, highly diverging ftsI alleles accounted for 61% of the rPBP3 isolates. The most prevalent substitution pattern (PBP3 type A) was present in 41% of rPBP3 isolates, mainly carried by ST367 and ST14. Several unrelated STs possessed identical copies of the ftsI allele encoding PBP3 type A. Infection sites, age groups, hospitalization rates and rPBP3 frequencies differed between STs and phylogenetic groups. Conclusions This study is the first to link ftsI alleles to STs in H. influenzae. The results indicate that horizontal gene transfer contributes to the emergence of rPBP3 by phylogeny restricted transformation. Clonally related virulent rPBP3 strains are widely disseminated and high-level resistant isolates emerge in new geographical regions, threatening current empiric antibiotic treatment. The need of continuous monitoring of beta-lactam susceptibility and a global system for molecular surveillance of rPBP3 strains is underlined. Combining MLST and ftsI/PBP3 typing is a powerful tool for this purpose.

• Nasser, *; Beres, S; Olsen, R; Dean, M; Rice, K & Long, S [Show all 19 contributors for this article] (2014). Evolutionary pathway to increased virulence and epidemic group A Streptococcus disease derived from 3,615 genome sequences. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 111(17), p. E1768–E1776. doi: 10.1073/pnas.1403138111. Full text in Research Archive
• Eldholm, Vegard; Norheim, Gunnstein; Lippe, Bent von der; Kinander, Wibeke; Dahle, Ulf R & Caugant, Dominique A [Show all 10 contributors for this article] (2014). Evolution of extensively drug-resistant Mycobacterium tuberculosis from a susceptible ancestor in a single patient. Genome Biology. ISSN 1465-6906. 15(11). doi: 10.1186/s13059-014-0490-3. Full text in Research Archive Show summary

  Background Mycobacterium tuberculosis is characterized by a low mutation rate and a lack of genetic recombination. Yet, the rise of extensively resistant strains paints a picture of a microbe with an impressive adaptive potential. Here we describe the first documented case of extensively drug-resistant tuberculosis evolved from a susceptible ancestor within a single patient. Results Genome sequences of nine serial M. tuberculosis isolates from the same patient uncovered a dramatic turnover of competing lineages driven by the emergence, and subsequent fixation or loss of single nucleotide polymorphisms. For most drugs, resistance arose through independent emergence of mutations in more than one clone, of which only one ultimately prevailed as the clone carrying it expanded, displacing the other clones in the process. The vast majority of mutations identified over 3.5 years were either involved in drug resistance or hitchhiking in the genetic background of these. Additionally, RNA-sequencing of isolates grown in the absence of drug challenge revealed that the efflux-associated iniBAC operon was up-regulated over time, whereas down-regulated genes include those involved in mycolic acid synthesis. Conclusions We observed both rapid acquisitions of resistance to antimicrobial compounds mediated by individual mutations as well as a gradual increase in fitness in the presence of antibiotics, likely driven by stable gene expression reprogramming. The rapid turnover of resistance mutations and hitchhiking neutral mutations has major implications for inferring tuberculosis transmission events in situations where drug resistance evolves within transmission chains.

• Lund, Vidar; Fonahn, Wenche; Pettersen, Jens Erik; Caugant, Dominique A; Ask, Eirik & Nysæter, Åse (2014). Detection of Legionella by cultivation and quantitative real-time polymerase chain reaction in biological waste water treatment plants in Norway. Journal of Water and Health. ISSN 1477-8920. 12(3), p. 543–554. doi: 10.2166/wh.2014.063. Full text in Research Archive

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• Topaz, Nadav; Caugant, Dominique Andree Yvette; Taha, Muhamed-Kheir; Brynildsrud, Ola Brønstad; Debech, Nadia & Hong, Eva [Show all 14 contributors for this article] (2020). Corrigendum to “Phylogenetic relationships and regional spread of meningococcal strains in the meningitis belt, 2011–2016” (EBioMedicine (2019) 41 (488–496), (S2352396419301331), (10.1016/j.ebiom.2019.02.054)). EBioMedicine. 51. doi: 10.1016/j.ebiom.2019.11.025. Full text in Research Archive
• Simonsen, Gunnar Skov; Blix, Hege Salvesen; Helgesen, Kari Marie Olli; Urdahl, Anne Margrete; Afset, Jan Egil & Andersen, Cecilie Torp [Show all 23 contributors for this article] (2025). NORM/NORM-VET 2024. Usage of Antimicrobial Agents and Occurrence of Antimicrobial Resistance in Norway. Veterinærinstituttet. doi: https:/www.vetinst.no/overvaking/antibiotikaresistens-norm-vet/_/attachment/inline/78155e88-2b2e-42a1-ac0c-b06071eb0479:21bb52d0f6c051c93f0d4a0605eb001e25e7fe99/NORM%20NORM-VET%202023%20(2).pdf. Full text in Research Archive
• Bruun, Tone; Børud, Bente; Caugant, Dominique Andree Yette; Kløvstad, Hilde; Olsen, Anne Olaug & Pires, Joao Pedro Do Couto [Show all 8 contributors for this article] (2025). Blod- og seksuelt overførbare infeksjoner. Årsrapport 2024. Folkehelseinstituttet. ISSN 9788284064987. Full text in Research Archive
• Bruun, Tone; Caugant, Dominique Andree Yette; Kløvstad, Hilde; Labberton, Angela Susan; Nilsen, Øivind & Olsen, Anne Olaug [Show all 9 contributors for this article] (2024). Blod- og seksuelt overførbare infeksjoner i Norge. Årsrapport 2023. Folkehelseinstituttet. ISSN 9788284064468. Full text in Research Archive
• Caugant, Dominique Andree Yvette; Kløvstad, Hilde; Nilsen, Øivind Jul & Olsen, Anne Olaug (2023). Overvåkning av seksuelt overførbare infeksjoner. Årsrapport 2022. Folkehelseinstituttet. Full text in Research Archive Show summary

  • I 2022 ble det meldt 29 271 tilfeller av klamydiainfeksjoner i Norge, 540 per 100 000 innbyggere. Personer under 25 år utgjorde 67 % av alle tilfellene. Etter en stigende trend i årene før pandemien, var det en liten nedgang i 2020 og 2021. Fra august 2022 har antall påviste tilfeller vært høyere enn foregående år. For året sett under ett, ses den største økningen i aldergruppen i 20-24 år. Situasjonen sammenfaller med en tilsvarende observert økning i meldte gonoretilfeller blant unge heteroseksuelt smittede. • Hiv-situasjonen er nå preget av et stort antall hiv-positive flyktninger/innvandrere som kommer til Norge. Det ble i 2022 meldt 245 hivtilfeller mot 102 i 2021. Av de 245 tilfellene var hele 192 (78 %) smittet før ankomst Norge, hvorav 97 kom fra Ukraina. Mest utsatt for hivsmitte er fortsatt menn som har sex med menn (msm) og heteroseksuelle menn på reise i utlandet, særlig til Sørøst-Asia. Det er fortsatt stabil, lav hiv-forekomst blant personer som tar stoff med sprøyter, blant norskfødte kvinner og blant ungdom. Totalt er det meldt 7125 hivpositive i Norge siden 1984, 4 785 menn og 2 340 kvinner, og det lever om lag 4 800 med diagnosen i Norge i dag. • Etter en kraftig nedgang i meldte gonoré tilfeller under pandemien gikk antall tilfeller igjen sterkt opp i 2022. Det ble i 2022 meldt 1857 gonorétilfeller mot 555 tilfeller i 2021. Spesielt stor er økningen blant unge kvinner i forhold til situasjonen før pandemien. Av de meldte tilfellene i 2022 er 48 % bosatt i Oslo. Samlet var det 1358 menn og 499 kvinner som ble meldt smittet. Av mennene var 1011 (74 %) smittet homoseksuelt og 347 heteroseksuelt. Blant msm forekommer en høy andel av tilfellene blant innvandrere bosatt i Norge. Utviklingen i 2022 reflekterer trolig full gjenåpning av samfunnet og økt sosial kontakt etter pandemien. Gonokokker har høy smittsomhet og spredningspotensialet er derfor høyt når mikroben nå er introdusert blant ungdom og unge heteroseksuelle der hyppigere partnerbytte og lav kondombruk er mer vanlig. I nåværende situasjon anbefaler vi lav terskel for gonoretesting samtidig med klamydiatest til tenåringer og unge voksne ved partnerbytte. • Etter det som trolig var en koronarelatert nedgang i syfilis i 2021 økte antall meldte tilfeller både blant msm og heteroseksuelt smittede i 2022. Det ble meldt 192 tilfeller av syfilis mot 163 tilfeller i 2021. Av tilfellene i 2022 var 163 (85 %) homoseksuelt smittet og 29 heteroseksuelt smittet. De 192 tilfellene fordeler seg på 184 menn og åtte kvinner. 57 % av de smittede er født i Norge og 107 (56 %) er hjemmehørende i Oslo. Fortsatt smittes flest msm ved tilfeldig sex i Oslo. Spesielt er msm med innvandrerbakgrunn og hivpositive utsatt for syfilissmitte. • Lymfogranuloma venerum (LGV) er en infeksjon med spesielle serotyper av klamydiabakterien. Det ble i 2022 meldt 36 tilfeller av LGV i Norge. Dermed er smittesituasjonen tilbake til slik den var før pandemien. I 2021 ble det meldt kun 10 tilfeller. Alle tilfellene ses blant msm, hvorav de fleste er smittet i Oslo og vel halvparten har innvandrerbakgrunn.

• Simonsen, Gunnar Skov; Blix, Hege Salvesen; Grave, Kari; Urdahl, Anne Margrete; Akselsen, Per Espen & Andersen, Cecilie Torp [Show all 9 contributors for this article] (2022). NORM/NORM-VET 2021: Usage of Antimicrobial Agents and Occurrence of Antimicrobial Resistance in Norway. Veterinærinstituttet. Full text in Research Archive Show summary

  Veterinærinstituttet overvåker forekomst av antibiotikaresistens i mikrober fra fôr, dyr og næringsmidler på oppdrag fra Mattilsynet. Dette gjøres i regi av NORM-VET, som er forkortelse for «Norsk overvåkingsprogram for antibiotikaresistens i mikrober fra fôr, dyr og næringsmidler». Data fra NORM-VET publiseres i den årlige NORM/NORM-VET rapporten som presenterer data om forekomst av antibiotikaresistens og forbruk av antibiotika både til dyr og mennesker.<p> <p>Formålet med å overvåke antibiotikaresistens er å få kunnskap om forekomst av antibiotikaresistens, samt følge trender over tid slik at endringer i forekomst eller bakenforliggende mekanismer fanges opp. Data fra NORM-VET danner grunnlag for å beskrive sammenhengen mellom bruk av antimikrobielle midler og forekomst av resistens. Data benyttes også til risikovurderinger. I tillegg er NORM-VET viktig som grunnlag og utgangspunkt for videre forskning innen antibiotikaresistens-problematikken.<p> <p>Resultatene fra NORM-VET 2021 bekrefter at situasjonen i Norge er god. Forekomsten av multiresistente bakterier, altså resistens mot tre eller flere antibakterielle klasser, samt resistente bakterier av særlig interesse er fremdeles lav.

• Caugant, Dominique Andree Yvette; Kløvstad, Hilde; Nilsen, Øivind Jul & Olsen, Anne Olaug (2022). Overvåkning av seksuelt overførbare infeksjoner. Årsrapport 2021. Folkehelseinstituttet. Full text in Research Archive Show summary

  • Trenden med nedgang i meldte hivtilfeller fortsetter, og vi ser nå det laveste antall påviste tilfeller på mer enn 20 år. De medikamentelle forebyggingsstrategiene antas å være de viktigste årsaker til nedgangen, men koronatiltakene medreiserestriksjoner, nedstengning av uteliv og sosial distansering har trolig bidratt til ytterligere nedgang etter 2019. Av de 102 hivtilfellene meldt i 2021 var det 64 (62 %) menn og 38 kvinner. 67 av tilfellene var blant innvandrere smittet før ankomst Norge. Det er fortsatt stabil, lav hivforekomst blant personer som tar stoff med sprøyter, blant norskfødte kvinner og blant ungdom. Mest utsatt for hivsmitte er fortsatt menn som har sex med menn (msm) og heteroseksuelle menn på reise i utlandet, særlig til Sørøst-Asia. Totalt er det meldt 6880 hivpositive i Norge siden 1985, 4 649 menn og 2 231 kvinner, og det lever om lag 4 500 med diagnosen i Norge i dag. • Den kraftige nedgangen i meldte gonorétilfeller de to siste årene er trolig et resultat av koronatiltakene som ble iverksatt i 2020. I 2021 ble det meldt 555 gonorétilfeller i Norge mot 1045 i 2020 og 1704 tilfeller i 2019. Nedgangen kommer både blant msm og blant heteroseksuelt smittede menn og kvinner. Det blir nå viktig å overvåke den videre utviklingen når samfunnet har åpnet opp. Av alle tilfellene er 52 % bosatt i Oslo og 56 % er født i Norge. Blant msm forekommer en høy andel av tilfellene blant innvandrere bosatt i Norge. • Etter en markant økning av syfilis i 2020 (noe overraskende i lys av koronarestriksjonene) ble det observert en betydelig nedgang i meldte syfilistilfeller både blant msm og heteroseksuelt smittede i 2021. Det ble meldt 163 tilfeller i 2021 mot 287 tilfeller i 2020. De 163 tilfellene fordeler seg på 159 menn og fire kvinner. 56 % av de smittede er født i Norge. Fortsatt smittes de fleste msm ved tilfeldig sex i Oslo. Spesielt er msm med innvandrerbakgrunn og hivpositive utsatt for syfilissmitte. • I 2021 ble det meldt 23 447 tilfeller av klamydiainfeksjoner i Norge, 435 per 100 000 innbyggere. Etter en stigende trend i årene før pandemien, var det en nedgang i 2020 (25 444 meldte tilfeller) som trolig knyttes til koronatiltakene. Nedgangen har fortsatt i 2021. Antall testede i 2021 var 390 692 for hele landet. Det viser at testaktiviteten er tilbake til samme nivå som før pandemien. Det er fortsatt flest meldte tilfeller i aldersgruppene under 25 år. Det er derfor viktig å målrette prøvetakingen til grupper med høyest risiko for smitte. • Lymfogranuloma venerum (LGV) er en seksuelt overførbar infeksjon som skyldes smitte med spesielle serotyper av klamydiabakterien. Det ble i 2021 meldt 10 tilfeller av LGV i Norge mot 14 tilfeller i 2020. Alle tilfellene ses blant godt voksne msm, hvorav de fleste er smittet i Oslo og mange har innvandrerbakgrunn.

• Caugant, Dominique Andree Yvette; Kløvstad, Hilde; Nilsen, Øivind Jul; Olsen, Anne Olaug & Whittaker, Robert Neil (2021). Overvåkning av seksuelt overførbare infeksjoner. Årsrapport 2020. Folkehelseinstituttet, Område for smittevern, miljø og helse. Full text in Research Archive
• Caugant, Dominique Andree Yvette; Kløvstad, Hilde; Nilsen, Øivind Jul & Whittaker, Robert Neil (2020). Overvåkning av seksuelt overførbare infeksjoner. Årsrapport 2019. Folkehelseinstituttet, Område for smittevern, miljø og helse. Full text in Research Archive
• Blystad, Hans Henrik; Caugant, Dominique Andree Yvette; Kløvstad, Hilde; Nilsen, Øivind Jul & Rykkvin, Rikard (2019). Overvåkning av seksuelt overførbare infeksjoner og blodbårne hepatitter. Årsrapport 2018. Folkehelseinstituttet. Full text in Research Archive Show summary

  • Siden antall meldte hiv-tilfeller nådde en topp i 2008 med 299 tilfeller har antall meldte tilfeller gradvis gått ned til 191 tilfeller i 2018. Nedgangen har særlig kommet blant norskfødte msm og heteroseksuelt smittede innvandrere smittet før ankomst til Norge. Det er fortsatt en stabil lav hivforekomst blant personer som tar stoff med sprøyter, blant norskfødte kvinner og blant ungdom. • De siste års utvikling med sterkt økende forekomst av gonoré blant menn som har sex med menn fortsatte i 2018. Også blant heteroseksuelle kvinner og menn har gonoré økt betydelig de senere årene. Situasjonen i Norge følger en internasjonal trend der gonoré øker kraftig i mange vestlige land. • Fra slutten av 1990-tallet har antall syfilistilfeller blant menn som har sex med menn økt betydelig i Norge og denne trenden fortsatte i 2018. Også blant heteroseksuelle kvinner og menn har forekomsten av syfilis økt de senere årene, men antall meldte tilfeller gikk noe ned i 2018. • Den rapporterte forekomsten av klamydia økte fra årtusenskiftet fram til 2008 for deretter å ha vært stabil gjennom flere år. I 2018 ble det diagnostisert 26 570 tilfeller, 502 per 100 000 innb. Det ble spesielt observert en økning i aldersgruppen 20-24 år det siste året. De siste årene har det vært en økning i antall undersøkelser samtidig som man finner færre blant de som testes. Fra 2017 til 2018 var det imidlertid en liten nedgang i antall undersøkte. • De siste årene er det årlig blitt meldt 15-33 tilfeller av lymfogranuloma venerum (LGV). Siden 2015 har antall tilfeller økt årlig og i 2018 ble det meldt 44 tilfeller, alle menn. Det er grunn til å tro at tilfellene hovedsakelig var blant menn som har sex med menn (msm). • Hepatitt C-situasjonen i Norge domineres av kroniske infeksjoner hos norskfødte hvor de aller fleste er antatt smittet gjennom tidligere eller pågående injiserende rusbruk. Anslag over antall personer som tar stoff med sprøyter har vist en nedgang de senere årene. I tillegg har antall hepatitt C-smittede som blir behandlet vist en betydelig øking siste år. Det grunn til å tro at antall nysmittede med hepatitt C er redusert de siste årene. • Hepatitt B-situasjonen domineres av at det årlig meldes 500-700 tilfeller av kronisk infeksjon, i all hovedsak blant nyankommede innvandrere fra høyendemiske land. Meldte tilfeller har gått betydelig ned siste årene i takt med redusert innvandring. Antall nydiagnostiserte tilfeller av akutt hepatitt B er stabilt på et lavt nivå. Overføring av akutt hepatitt B ved andre smittemåter enn sprøyter og sex er uvanlig i Norge. • Nasjonale strategier mot hepatitt ble publisert i 2016 og 2018. Som en følge av dette ble hepatitt B-vaksine innført i barnevaksinasjonsprogrammet i 2016, alle gravide ble fra juni 2018 tilbudt testing for hepatitt B-virus og det ble i 2019 utarbeidet en implementeringsplan for å nå målene om at forekomsten av hepatitt C i Norge skal reduseres med 90 % innen 2023 sammenlignet med 2018 og at ingen i Norge skal dø eller bli alvorlig syk av hepatitt C.

• Berg, Are Stuwitz; Berild, Jacob Dag; Caugant, Dominique Andree Yvette; Haugen, Inger Lise; Konsmo, Kirsten & Steinbakk, Martin [Show all 9 contributors for this article] (2018). Årsrapport 2017 Invasive infeksjoner. Folkehelseinstituttet. Full text in Research Archive
• Vollan, Hilde Synnøve; Bukholm, Geir; Caugant, Dominique A; Tannæs, Tone Møller & Vriend, Gerrit (2018). In silico analyzes of porins involved in niche adaptation: Exploring the role of Helicobacter pylori outer membrane phospholipase A in acid tolerance. Universitetet i Oslo. Full text in Research Archive Show summary

  Helicobacter pylori is an ulcer-causing bacterium that evolutionary needs to adapt quickly to changing conditions. Hilde Synnøve Vollan’s bioinformatics studies revealed that H. pylori outer membrane phospholipase A (OMPLA) is multifunctional with both enzymatic and pore activity. OMPLA is a protein found in a variety of bacterial species, and usually functions as an enzyme that degrades the outer membrane. Previous studies indicate that OMPLA must be intact for H. pylori survival in an acidic environment, while its enzymatic activity is not required. The present study presents the hypothesis that OMPLA is involved in acid management. Analyzes of the modeled H. pylori OMPLA 3D structure indicate that the niche-adaption likely is urea-influx and ammonium-efflux. This model may be paradigmatic for all gastric Helicobacter species. This work will be used in future studies aimed at preventing ulcers and gastric cancers caused by H. pylori.

• Berg, Are Stuwitz; Caugant, Dominique Andree Yvette; Haugen, Inger Lise; Konsmo, Kirsten; Steinbakk, Martin & Storsæter, Jann [Show all 9 contributors for this article] (2017). Årsrapport for 2016 - Invasive infeksjoner. Folkehelseinstituttet. Full text in Research Archive
• Caugant, Dominique Andree Yvette; Haugen, Inger Lise; Konsmo, Kirsten; Nordstrand, Karine; Steinbakk, Martin & Storsæter, Jann [Show all 8 contributors for this article] (2016). Invasive infeksjoner. Årsrapport for 2015. Folkehelseinstituttet. Full text in Research Archive
• Caugant, Dominique Andree Yvette; Haugen, Inger Lise; Konsmo, Kirsten; Nordstrand, Karine; Steinbakk, Martin & Storsæter, Jann [Show all 8 contributors for this article] (2015). Invasive infeksjoner. Årsrapport 2014. Folkehelseinstituttet, Divisjon for Smittevern. Full text in Research Archive
• Andersen, Cecilie Torp; Simonsen, Gunnar Skov; Arnesen, Trude Margrete; Urdahl, Anne Margrete; Astrup, Elisabeth & Blix, Hege Salvesen [Show all 18 contributors for this article] (2015). NORM/NORM-VET 2014. Usage of Antimicrobial Agents and Occurrence of Antimicrobial Resistance in Norway. NORM/NORM-VET. Full text in Research Archive
• Blystad, Hans Henrik; Caugant, Dominique A; Flem, Elmira; Haugen, Inger Lise; Næss, Lisbeth Meyer & Nøkleby, Hanne Magdalene (2014). Meningokokksykdom i Norge og anbefalinger for bruk av meningokokkvaksiner. Folkehelseinstituttet. ISSN 9788280826213. Full text in Research Archive

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