Truls Michael Leegaard

• Bøås, Håkon; Havdal, Lise Beier; Størdal, Ketil; Døllner, Henrik; Leegaard, Truls Michael & Bekkevold, Terese [Vis alle 14 forfattere av denne artikkelen] (2024). No association between disease severity and respiratory syncytial virus subtypes RSV-A and RSV-B in hospitalized young children in Norway. PLOS ONE. ISSN 1932-6203. 19(3). doi: 10.1371/journal.pone.0298104. Fulltekst i vitenarkiv
• Garcia Llorente, Ignacio; Lee, Yunsung; Brynildsrud, Ola Brønstad; Eldholm, Vegard; Magnus, Per Minor & Blomfeldt, Anita [Vis alle 10 forfattere av denne artikkelen] (2023). Tracing the adaptive evolution of SARS-CoV-2 during vaccine roll-out in Norway. Virus Evolution. ISSN 2057-1577. 10(1). doi: 10.1093/ve/vead081.
• Dyrhovden, Ruben; Eagan, Tomas Mikal Lind; Fløtten, Øystein; Siljan, William Ward; Leegaard, Truls Michael & Bø, Bjørnar [Vis alle 17 forfattere av denne artikkelen] (2023). Pleural Empyema Caused by Streptococcus intermedius and Fusobacterium nucleatum: A Distinct Entity of Pleural Infections. Clinical Infectious Diseases. ISSN 1058-4838. 77(10), s. 1361–1371. doi: 10.1093/cid/ciad378. Fulltekst i vitenarkiv
• Leegaard, Truls Michael; Justesen, Ulrik S.; Matuschek, Erika & Giske, Christian G. (2023). Performance of automated antimicrobial susceptibility testing for the detection of antimicrobial resistance in gram-negative bacteria: a NordicAST study. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 131(10), s. 543–551. doi: 10.1111/apm.13346. Fulltekst i vitenarkiv
• Corwin, Linn Merete B.; Campbell, Patricia; Jakobsen, Kirsti; Müller, Fredrik; Lai, Xiaoran & Unemo, M. [Vis alle 9 forfattere av denne artikkelen] (2023). Improvement in Neisseria gonorrhoeae culture rates by bedside inoculation and incubation at a clinic for sexually transmitted infections. Annals of Clinical Microbiology and Antimicrobials. ISSN 1476-0711. 22. doi: 10.1186/s12941-023-00576-0. Fulltekst i vitenarkiv
• Selvakumar, Joel Pradeepkumar; Havdal, Lise Beier; Drevvatne, Martin Solstrand; Brodwall, Elias Myrstad; Lund-Berven, Lise & Stiansen-Sonerud, Tonje [Vis alle 19 forfattere av denne artikkelen] (2023). Prevalence and Characteristics Associated With Post-COVID-19 Condition Among Nonhospitalized Adolescents and Young Adults. JAMA Network Open. ISSN 2574-3805. 6(3). doi: 10.1001/jamanetworkopen.2023.5763. Fulltekst i vitenarkiv
• Sommen, Silke Lauren; Havdal, Lise Beier; Selvakumar, Joel Pradeepkumar; Einvik, Gunnar; Leegaard, Truls Michael & Lund-Johansen, Fridtjof [Vis alle 12 forfattere av denne artikkelen] (2022). Inflammatory markers and pulmonary function in adolescents and young adults 6 months after mild COVID-19. Frontiers in Immunology. ISSN 1664-3224. 13, s. 1–12. doi: 10.3389/fimmu.2022.1081718. Fulltekst i vitenarkiv
• Havdal, Lise Beier; Berven, Lise; Selvakumar, Joel Pradeepkumar; Stiansen-Sonerud, Tonje; Leegaard, Truls Michael & Tjade, Trygve Olav [Vis alle 9 forfattere av denne artikkelen] (2022). Neurological Involvement in COVID-19 Among Non-Hospitalized Adolescents and Young Adults. Frontiers in Neurology. ISSN 1664-2295. 13. doi: 10.3389/fneur.2022.915712. Fulltekst i vitenarkiv
• Bøås, Håkon; Bekkevold, Terese; Havdal, Lise Beier; Kran, Anne-Marte Bakken; Rojahn, Astrid & Størdal, Ketil [Vis alle 16 forfattere av denne artikkelen] (2022). The burden of hospital-attended influenza in Norwegian children. Frontiers in pediatrics. ISSN 2296-2360. 10. doi: 10.3389/fped.2022.963274. Fulltekst i vitenarkiv
• Eskild, Anne; Mørkrid, Lars; Mortensen, Siri Beisland & Leegaard, Truls Michael (2022). Prevalence of antibodies against SARS-CoV-2 among pregnant women in Norway during the period December 2019 through December 2020. Epidemiology and Infection. ISSN 0950-2688. 150, s. 1–3. doi: 10.1017/S0950268822000073. Fulltekst i vitenarkiv Vis sammendrag

  We studied severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence among pregnant women in Norway by including all women who were first trimester pregnant (n = 6520), each month from December 2019 through December 2020, in the catchment region of Norway's second-largest hospital. We used sera that had been frozen stored after compulsory testing for syphilis antibodies in antenatal care. The sera were analysed with the Elecsys® Anti-SARS-CoV-2 immunoassay (Roche Diagnostics, Cobas e801). This immunoassay detects IgG/IgM against SARS-CoV-2 nucleocapsid antigen. Sera with equivocal or positive test results were retested with the Liaison® SARS-CoV-2 S1/S2 IgG (DiaSorin), which detects IgG against the spike (S)1 and S2 protein on the SARS-CoV-2 virus. In total, 98 women (adjusted prevalence 1.7%) had SARS CoV-2 antibodies. The adjusted seroprevalence increased from 0.3% (1/445) in December 2019 to 5.7% (21/418) in December 2020. Out of the 98 seropositive women, 36 (36.7%) had serological signs of current SARS-CoV-2 infection at the time of serum sampling, and the incidence remained low during the study period. This study suggests that SARS CoV-2 was present in the first half of December 2019, 6 weeks before the first case was recognised in Norway. The low occurrence of SARS-CoV-2 infection during 2020, may be explained by high compliance to extensive preventive measures implemented early in the epidemic.

• Berven, Lise; Selvakumar, Joel Pradeepkumar; Havdal, Lise Beier; Stiansen-Sonerud, Tonje; Einvik, Gunnar & Leegaard, Truls Michael [Vis alle 10 forfattere av denne artikkelen] (2022). Inflammatory Markers, Pulmonary Function, and Clinical Symptoms in Acute COVID-19 Among Non-Hospitalized Adolescents and Young Adults. Frontiers in Immunology. ISSN 1664-3224. 13:837288, s. 1–11. doi: 10.3389/fimmu.2022.837288. Fulltekst i vitenarkiv
• Gibory, Moustafa; Bruun, Tone; Flem, Elmira; Dembinski, Jennifer Lynn; Haltbakk, Ildri & Størdal, Ketil [Vis alle 11 forfattere av denne artikkelen] (2021). Genetic diversity of rotavirus strains circulating in Norway before and after the introduction of rotavirus vaccination in children. Journal of Medical Virology. ISSN 0146-6615. 00, s. 1–8. doi: 10.1002/jmv.27484. Fulltekst i vitenarkiv
• Doyle, Maeve; Boyle, Breida; Brennan, Caoimhe; Holland, Jane; Mifsud, Albert & Hell, Markus [Vis alle 8 forfattere av denne artikkelen] (2021). Specialist training in medical microbiology across Europe in 2021—an update on the actual training situation based on a survey. Clinical Microbiology and Infection (CMI). ISSN 1198-743X. 27(11), s. 1576–1580. doi: 10.1016/j.cmi.2021.06.027.
• Beeching, Nicholas J.; Rautelin, Hilpi; Stahl, Jean-Paul & Leegaard, Truls Michael (2021). Training and assessment of medical specialists in clinical microbiology and infectious diseases in Europe. Clinical Microbiology and Infection (CMI). ISSN 1198-743X. 27(11), s. 1581–1588. doi: 10.1016/j.cmi.2021.07.009.
• Bruun, Tone; Valcarcel Salamanca, Beatriz; Bekkevold, Terese; Døllner, Henrik; Gibory, Moustafa & Gilje, Ann Marit [Vis alle 14 forfattere av denne artikkelen] (2021). Impact of the Rotavirus Vaccination Program in Norway after Four Years with High Coverage. The Pediatric Infectious Disease Journal. ISSN 0891-3668. s. 368–374. doi: 10.1097/INF.0000000000003020. Fulltekst i vitenarkiv
• Noone, John Christopher; Helmersen, Karin; Leegaard, Truls Michael; Skråmm, Inge & Aamot, Hege Vangstein (2021). Rapid Diagnostics of Orthopaedic-Implant-Associated Infections Using Nanopore Shotgun Metagenomic Sequencing on Tissue Biopsies . Microorganisms. ISSN 2076-2607. 9(1). doi: 10.3390/microorganisms9010097. Fulltekst i vitenarkiv
• Aamot, Hege Vangstein; Noone, John Christopher; Skråmm, Inge & Leegaard, Truls Michael (2020). Are conventional microbiological diagnostics sufficiently expedient in the era of rapid diagnostics? Evaluation of conventional microbiological diagnostics of orthopedic implant-associated infections (OIAI). Acta Orthopaedica. ISSN 1745-3674. 91, s. 1–4. doi: 10.1080/17453674.2020.1844499. Fulltekst i vitenarkiv
• Berg, Are Stuwitz; Inchley, Christopher; Fjærli, Hans Olav; Leegaard, Truls Michael & Nakstad, Britt (2020). Assessing Severity in Pediatric Pneumonia: Predictors of the Need for Major Medical Interventions. Pediatric emergency care. ISSN 0749-5161. doi: 10.1097/PEC.0000000000001179.
• Ingvaldsen, Christoffer Aam; Leegaard, Truls Michael; Kravdal, Gunnhild & Mørk, Cato (2019). Infectious pseudochromhidrosis: A case report and literature review. Acta Dermato-Venereologica. ISSN 0001-5555. 100:adv00005(1), s. 1–7. doi: 10.2340/00015555-3338. Fulltekst i vitenarkiv
• Di Ruscio, Francesco; Guzzetta, Giorgio; Bjørnholt, Jørgen; Leegaard, Truls Michael; Moen, Aina Elisabeth Fossum & Merler, Stefano [Vis alle 7 forfattere av denne artikkelen] (2019). Quantifying the transmission dynamics of MRSA in the community and healthcare settings in a low-prevalence country. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 116(29), s. 14599–14605. doi: 10.1073/pnas.1900959116. Fulltekst i vitenarkiv
• Kristiansen, Miriam Skjerven; Stabursvik, Julie; O'Leary, Elise Catriona Solberg; Pedersen, Maria; Asprusten, Tarjei Tørre & Leegaard, Truls Michael [Vis alle 11 forfattere av denne artikkelen] (2019). Clinical symptoms and markers of disease mechanisms in adolescent chronic fatigue following Epstein-Barr virus infection: An exploratory cross-sectional study. Brain, Behavior, and Immunity. ISSN 0889-1591. 80, s. 551–563. doi: 10.1016/j.bbi.2019.04.040. Fulltekst i vitenarkiv
• Lepuschitz, Sarah; Ruppitsch, Werner; Pekard-Amenitsch, Shiva; Forsythe, Stephen J.; Cormican, Martin & Mach, Robert L. [Vis alle 31 forfattere av denne artikkelen] (2019). Multicenter study of Cronobacter sakazakii infections in humans, Europe, 2017. Emerging Infectious Diseases. ISSN 1080-6040. 25(3), s. 515–522. doi: 10.3201/eid2503.181652.
• Pedersen, Maria; Asprusten, Tarjei Tørre; Godang, Kristin; Leegaard, Truls Michael; Osnes, Liv T. N. & Skovlund, Eva [Vis alle 9 forfattere av denne artikkelen] (2019). Fatigue in Epstein-Barr virus infected adolescents and healthy controls: A prospective multifactorial association study. Journal of Psychosomatic Research. ISSN 0022-3999. 121, s. 46–59. doi: 10.1016/j.jpsychores.2019.04.008.
• Pedersen, Maria; Asprusten, Tarjei Tørre; Godang, Kristin; Leegaard, Truls Michael; Osnes, Liv T. N. & Skovlund, Eva [Vis alle 9 forfattere av denne artikkelen] (2019). Lifestyle factors during acute Epstein-Barr virus infection in adolescents predict physical activity six months later. Acta Paediatrica. ISSN 0803-5253. 108(8), s. 1521–1526. doi: 10.1111/apa.14728. Fulltekst i vitenarkiv
• Espenhain, Laura Elisabeth; Jørgensen, Silje Bakken; Leegaard, Truls Michael; Lelek, Michaela Marie; Hänsgen, Siri Haug & Nakstad, Britt [Vis alle 8 forfattere av denne artikkelen] (2018). Travel to Asia is a strong predictor for Carriage of cephalosporin resistant E. coli and Klebsiella spp. but does not explain everything; prevalence study at a Norwegian hospital 2014-2016. Antimicrobial Resistance and Infection Control. ISSN 2047-2994. 7. doi: 10.1186/s13756-018-0429-7. Fulltekst i vitenarkiv
• Pedersen, Maria; Asprusten, Tarjei Tørre; Godang, Kristin; Leegaard, Truls Michael; Osnes, Liv T. N. & Skovlund, Eva [Vis alle 9 forfattere av denne artikkelen] (2018). Predictors of chronic fatigue in adolescents six months after acute Epstein-Barr virus infection: a prospective cohort study. Brain, Behavior, and Immunity. ISSN 0889-1591. 75, s. 94–100. doi: 10.1016/j.bbi.2018.09.023. Fulltekst i vitenarkiv
• Tunsjø, Hege; Kalyanasundaram, Sumana; Charnock, Colin; Leegaard, Truls Michael & Moen, Aina Elisabeth Fossum (2018). Challenges in the identification of methicillin-resistant Staphylococcus argenteus by routine diagnostics. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 126(6), s. 533–537. doi: 10.1111/apm.12843.
• Di Ruscio, Francesco; Bjørnholt, Jørgen; Larssen, Kjersti Wik; Leegaard, Truls Michael; Moen, Aina Elisabeth Fossum & De Blasio, Birgitte Freiesleben (2018). Epidemiology and spa-type diversity of meticillin-resistant Staphylococcus aureus in community and healthcare settings in Norway. Journal of Hospital Infection. ISSN 0195-6701. doi: 10.1016/j.jhin.2017.12.019. Fulltekst i vitenarkiv
• Inchley, Christopher; Berg, Are Stuwitz; Vahdani-Benam, Afsaneh; Kvissel, Anne Katrine; Leegaard, Truls Michael & Nakstad, Britt (2017). Mycoplasma Pneumoniae: A Cross-sectional Population-based Comparison of Disease Severity in Preschool and School-age Children. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 36(10), s. 930–936. doi: 10.1097/INF.0000000000001628.
• Jørgensen, Silje; Søraas, Arne Vasli; Arnesen, Lotte Pia Stenfors; Leegaard, Truls Michael; Sundsfjord, Arnfinn & Jenum, Pål (2017). First environmental sample containing plasmid-mediated colistin-resistant ESBL-producing Escherichia coli detected in Norway. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 125(9), s. 822–825. doi: 10.1111/apm.12720. Fulltekst i vitenarkiv
• Jørgensen, Silje; Søraas, Arne Vasli; Arnesen, Lotte Pia Stenfors; Leegaard, Truls Michael; Sundsfjord, Arnfinn & Jenum, Pål (2017). A comparison of extended spectrum beta-lactamase producing Escherichia coli from clinical, recreational water and wastewater samples associated in time and location. PLOS ONE. ISSN 1932-6203. 12(10). doi: 10.1371/journal.pone.0186576. Fulltekst i vitenarkiv
• Holmøy, Trygve; Gythfeldt, Hedda & Leegaard, Truls Michael (2017). Listeria monocytogenes infection associated with alemtuzumab - - a case for better preventive strategies. BMC Neurology. ISSN 1471-2377. 17(65). doi: 10.1186/s12883-017-0848-8.
• Johnsen, Bjørn Odd; Handal, Nina; Meisal, Roger; Bjørnholt, Jørgen; Gaustad, Peter & Leegaard, Truls Michael (2017). erm gene distribution among Norwegian Bacteroides isolates and evaluation of phenotypic tests to detect inducible clindamycin resistance in Bacteroides species. Anaerobe. ISSN 1075-9964. 47, s. 226–232. doi: 10.1016/j.anaerobe.2017.06.004.
• Di Ruscio, Francesco; Bjørnholt, Jørgen; Leegaard, Truls Michael; Moen, Aina Elisabeth Fossum & De Blasio, Birgitte Freiesleben (2017). MRSA infections in Norway: A study of the temporal evolution, 2006-2015. PLOS ONE. ISSN 1932-6203. 12(6). doi: 10.1371/journal.pone.0179771. Fulltekst i vitenarkiv
• Berg, Are Stuwitz; Inchley, Christopher; Fjærli, Hans Olav; Leegaard, Truls Michael; Lindbæk, Morten & Nakstad, Britt (2017). Clinical features and inflammatory markers in pediatric pneumonia: a prospective study. European Journal of Pediatrics. ISSN 0340-6199. 176(5), s. 629–638. doi: 10.1007/s00431-017-2887-y.
• Jørgensen, Silje; Søraas, Arne Vasli; Sundsfjord, Arnfinn; Liestøl, Knut; Leegaard, Truls Michael & Jenum, Pål (2017). Fecal carriage of extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae after urinary tract infection - A three year prospective cohort study. PLOS ONE. ISSN 1932-6203. 12:e017w|(16), s. 13510–1. doi: 10.1371/journal.pone.0173510. Fulltekst i vitenarkiv
• Meisal, Roger; Rounge, Trine Ballestad; Christiansen, Irene Kraus; Eieland, Alexander Kirkeby; Worren, Merete Molton & Molden, Tor [Vis alle 10 forfattere av denne artikkelen] (2017). HPV Genotyping of Modified General Primer-Amplicons Is More Analytically Sensitive and Specific by Sequencing than by Hybridization. PLOS ONE. ISSN 1932-6203. 12(1). doi: 10.1371/journal.pone.0169074. Fulltekst i vitenarkiv
• Tunsjø, Hege; Kalyanasundaram, Sumana; Worren, Merete Molton; Leegaard, Truls Michael & Moen, Aina Elisabeth Fossum (2017). High frequency of occupied attB regions in Norwegian Staphylococcus aureus isolates supports a two-step MRSA screening algorithm. European Journal of Clinical Microbiology and Infectious Diseases. ISSN 0934-9723. 36(1), s. 65–74. doi: 10.1007/s10096-016-2771-0.
• Blomfeldt, Anita; Eskesen, Arne N; Aamot, Hege Vangstein; Leegaard, Truls Michael & Bjørnholt, Jørgen (2016). Population-based epidemiology of Staphylococcus aureus bloodstream infection: clonal complex 30 genotype is associated with mortality. European Journal of Clinical Microbiology and Infectious Diseases. ISSN 0934-9723. 35(5), s. 803–813. doi: 10.1007/s10096-016-2601-4.
• Blomfeldt, Anita; Aamot, Hege Vangstein; Eskesen, Arne N; Monecke, Stefan; White, Richard & Leegaard, Truls Michael [Vis alle 7 forfattere av denne artikkelen] (2016). DNA microarray analysis of Staphylococcus aureus causing bloodstream infection: bacterial genes associated with mortality? European Journal of Clinical Microbiology and Infectious Diseases. ISSN 0934-9723. 35(8), s. 1285–1295. doi: 10.1007/s10096-016-2663-3.
• Berg, Are Stuwits; Inchley, Christopher; Aase, Audun; Fjærli, Hans Olav; Bull, Reidun & Aaberge, Ingeborg Sundsvalen [Vis alle 8 forfattere av denne artikkelen] (2016). Etiology of Pneumonia in a Pediatric Population with High Pneumococcal Vaccine Coverage. A Prospective Study. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 35(3), s. e69–e75. doi: 10.1097/INF.0000000000001009. Vis sammendrag

  Background: Improved Childhood Immunizations Programs, especial ly the introduction of pneumococcal vaccination, better diagnostic methods and the importance of reduced antibiotic misuse, makes this a critical ti me to increase knowledge on the etiology of pediatric pneumonia. Our main objective was to identify the contribution of various microbiological species that causes pneumonia in previously healthy children and adolescents in a population with high pneumococcal conjugate vaccine coverage. Methods: This prospective, observational study enrolled pati ents with clinical and radiological signs of pneumonia over a 2-year period. Both in- and outpatients were included. Paired sera, nasopharyngeal PCR and bacterial cultures from blood and pleura were analyzed to detect potential viral and bacterial causative pathogens. Results: 265 cases of clinical and radiological verified pneumonia were identified. The pneumococcal vaccine coverage was 85%. We identified a causative pathogen in 84.2% of all cases; 63.4% with single viral etiology, 11.3% with pneumococcus and 7.5% with mycoplasma infection. Respiratory syncytial virus was the most common pathogen < 5 years, while mycoplasma was the most common in older children. Conclusions: We identified the majority of 265 cases with radiology proven pneumonia as single viral infections, predominantly respiratory syncytial virus, and a much lower proportion of bacterial causes. These findings may impact pneumonia Management Guidelines in areas where widespread pneumococcal vaccination is provided, and contribute to reduced antibiotic overuse in pediatric pneumonia.

• Moxnes, John Fredrik; Moen, Aina Elisabeth Fossum & Leegaard, Truls Michael (2015). Studying the time trend of Methicillinresistant Staphylococcus aureus (MRSA) in Norway by use of non-stationary γ-Poisson distributions. BMJ Open. ISSN 2044-6055. 5(10). doi: 10.1136/bmjopen-2014-007163. Fulltekst i vitenarkiv
• Tunsjø, Hege Smith; Kvissel, Anne Katrine; Follin-Arbelet, Benoit; Brotnov, Beth-Marie; Ranheim, Trond Egil & Leegaard, Truls Michael (2015). Suitability of stx-PCR directly from fecal samples in clinical diagnostics of STEC. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 123(10), s. 872–878. doi: 10.1111/apm.12428.
• Handal, Nina; Jørgensen, Silje; Tunsjø, Hege Smith; Johnsen, Bjørn Odd & Leegaard, Truls Michael (2015). Anaerobic blood culture isolates in a Norwegian university hospital: Identification by MALDI-TOF MS vs 16S rRNA sequencing and antimicrobial susceptibility profiles. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 123(9), s. 749–758. doi: 10.1111/apm.12410.
• Raastad, Ragnhild; Tvete, Ingunn Fride; Abrahamsen, Tore G; Berild, Dag; Leegaard, Truls Michael & Walberg, Mette [Vis alle 7 forfattere av denne artikkelen] (2015). A worrying trend in weight-adjusted paediatric antibiotic use in a Norwegian tertiary care hospital. Acta Paediatrica. ISSN 0803-5253. 104(7), s. 687–692. doi: 10.1111/apa.12994. Vis sammendrag

  Aim The World Health Organization recommends the defined daily dose (DDD) as the standard unit of measurement for antibiotic use, but this is not applicable in children. We aimed to assess paediatric antibiotic use in a Norwegian tertiary care hospital using a novel weight-adjusted method. Methods We obtained antibiotic purchase data from the hospital pharmacy and administrative data for all admissions from 2002 to 2009 to the paediatric wards at Oslo University Hospital, Rikshospitalet. Recommended daily doses per 100 kg days (RDDs/kg days) were calculated based on national guidelines for paediatric antibiotic use, length of stay and estimated weight for sex and age using national growth references. Results Total antibiotic use increased significantly from 51.8 to 65.5 RDDs/100 kg days. We found statistically significant annual increases in the consumption of carbapenems (18.0%), third-generation cephalosporins (6.0%) and imidazole derivatives (6.6%) and a considerable difference between total antibiotic use measured in RDDs/100 kg days and DDDs/100 bed days for neonates. Conclusion Weight-adjusted antibiotic use provided a more meaningful description of the quantities of antibiotics consumed than DDDs/100 bed days, particularly for neonates. Total antibiotic use, use of meropenem, third-generation cephalosporins and imidazole derivatives increased significantly despite low prevalence of antibiotic-resistant pathogens.

• Tunsjø, Hege Smith; Berg, Are Stuwits; Inchley, Christopher; Røberg, Irmelin Kittelsen & Leegaard, Truls Michael (2015). Comparison of nasopharyngeal aspirate with flocked swab for PCR-detection of respiratory viruses in children. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 123(6), s. 473–477. doi: 10.1111/apm.12375.
• Aase, Audun; Herstad, Tove Karin; Jørgensen, Silje Bakken; Leegaard, Truls Michael; Berbers, Guy & Steinbakk, Martin [Vis alle 7 forfattere av denne artikkelen] (2014). Anti-pertussis antibody kinetics following DTaP-IPV booster vaccination in Norwegian children 7-8 years of age. Vaccine. ISSN 0264-410X. 32(45), s. 5931–5936. doi: 10.1016/j.vaccine.2014.08.069.
• Jørgensen, Silje Bakken; Samuelsen, Ørjan; Sundsfjord, Arnfinn; Bhatti, Sidra Ahmad; Jørgensen, Ingvild Aalberg & Sivapathasundaram, Thusanth [Vis alle 7 forfattere av denne artikkelen] (2014). High prevalence of faecal carriage of ESBL-producing Enterobacteriaceae in Norwegian patients with gastroenteritis. Scandinavian Journal of Infectious Diseases. ISSN 0036-5548. 46(6), s. 462–465. doi: 10.3109/00365548.2014.896031.
• Hegstad, Kristin ; Giske, Christian G.; Haldorsen, Bjørg; Matuschek, Erika; Schønning, Kristian & Leegaard, Truls Michael [Vis alle 8 forfattere av denne artikkelen] (2014). Performance of the EUCAST disk diffusion method, the CLSI agar screen method, and the Vitek 2 automated antimicrobial susceptibility testing system for detection of clinical isolates of enterococci with low- and medium-level VanB-type vancomycin resistance: A multicenter study. Journal of Clinical Microbiology. ISSN 0095-1137. 52(5), s. 1582–1589. doi: 10.1128/JCM.03544-13. Fulltekst i vitenarkiv
• Aldrin, Magne; Raastad, Ragnhild; Tvete, Ingunn Fride; Berild, Dag; Frigessi, Arnoldo & Leegaard, Truls Michael [Vis alle 9 forfattere av denne artikkelen] (2013). Antibiotic resistance in hospitals: a ward-specific random effect model in a low antibiotic consumption environment. Statistics in Medicine. ISSN 0277-6715. 32(8), s. 1407–1418. doi: 10.1002/sim.5636. Vis sammendrag

  Association between previous antibiotic use and emergence of antibiotic resistance has been reported for several microorganisms. The relationship has been extensively studied, and although the causes of antibiotic resistance are multi-factorial, clear evidence of antibiotic use as a major risk factor exists. Most studies are carried out in countries with high consumption of antibiotics and corresponding high levels of antibiotic resistance, and currently, little is known whether and at what level the associations are detectable in a low antibiotic consumption environment. We conduct an ecological, retrospective study aimed at determining the impact of antibiotic consumption on antibiotic-resistant Pseudomonas aeruginosa in three hospitals in Norway, a country with low levels of antibiotic use. We construct a sophisticated statistical model to capture such low signals. To reduce noise, we conduct our study at hospital ward level. We propose a random effect Poisson or binomial regression model, with a reparametrisation that allows us to reduce the number of parameters. Inference is likelihood based. Through scenario simulation, we study the potential effects of reduced or increased antibiotic use. Results clearly indicate that the effects of consumption on resistance are present under conditions with relatively low use of antibiotic agents. This strengthens the recommendation on prudent use of antibiotics, even when consumption is relatively low.

• Moen, Aina Elisabeth Fossum; Tannæs, Tone Møller & Leegaard, Truls Michael (2013). USA300 methicillin-resistant Staphylococcus aureus in Norway. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 121(11), s. 1091–1096. doi: 10.1111/apm.12077.
• Tunsjø, Hege Smith; Follin-Arbelet, Benoit; Clausen, Nina Merethe; Ness, Yngve; Leegaard, Truls Michael & Bemanian, Vahid (2013). A rapid, high-throughput screening method for carriage of methicillin-resistant Stphylococcus ureus. APMIS - Journal of Pathologiy, Microbiology and Immunology. ISSN 0903-4641. 121(9), s. 865–870. doi: 10.1111/apm.12049.
• Moxnes, John Fredrik; De Blasio, Birgitte Freiesleben; Leegaard, Truls Michael & Moen, Aina Elisabeth Fossum (2013). Methicillin-Resistant Staphylococcus aureus (MRSA) Is Increasing in Norway: A Time Series Analysis of Reported MRSA and Methicillin-Sensitive S. aureus Cases, 1997–2010. PLOS ONE. ISSN 1932-6203. 8(8). doi: 10.1371/journal.pone.0070499.
• Samuelsen, Ørjan; Toleman, MA; Hasseltvedt, Viggo H; Fuursted, K; Leegaard, Truls Michael & Walsh, TR [Vis alle 8 forfattere av denne artikkelen] (2011). Molecular characterization of VIM-producing Klebsiella pneumoniae from Scandinavia reveals genetic relatedness with international clonal complexes encoding transferable multidrug resistance. Clinical Microbiology and Infection (CMI). ISSN 1198-743X. 17(12), s. 1811–1816. doi: 10.1111/j.1469-0691.2011.03532.x. Vis sammendrag

  VIM-producing Klebsiella pneumoniae (VPKP) has been identified as a source of hospital outbreaks and is prevalent particularly in the Mediterranean region. In this study we have characterized eight VPKP isolates identified in Scandinavia during 2005–2008. With the exception of one isolate, all were from patients with recent history of hospitalization abroad (Greece, n = 6; Turkey, n = 1). Multilocus sequence typing (MLST) resulted in five sequence types (STs), ST36 (n = 1), ST147 (n = 4), ST272 (n = 1), ST273 (n = 1) and ST383 (n = 1), which except for ST272 were part of putative international clonal complexes. All were multidrug resistant due to the presence of other resistance determinants, including extended-spectrum β-lactamases (CTX-M-3, SHV-5 and SHV-12), 16S rRNA methylases (ArmA) and plasmid-mediated quinolone resistance determinants (QnrS). One isolate harboured a novel VIM-variant (VIM-26) while VIM-1 and VIM-19 were detected in six and one isolate, respectively. Two different genetic structures surrounding the blaVIM gene were identified in four isolates. In two isolates blaVIM-1 and blaVIM-26 were located in an integron similar to In-e541 (intI1;blaVIM-1/-26;aacA7; dhfrI;aadA1;3′CS) while in the other two isolates blaVIM-1 was located in an integron lacking 3′CS but with an IS26 element in the 3′end (intI1;blaVIM-1;aac(6′)-Ib;IS26), as identified in the IncN plasmid pKOX105. The blaVIM-genes were located on transferable plasmids ranging from ∼40 to ∼240 kb and associated with Tn21 in four isolates. PCR-based replicon typing indicated association of blaVIM with IncN (n = 3) and A/C (n = 1) broad-host-range plasmids but also with unknown replicons (n = 4). In conclusion, Scandinavian VPKP is associated with importation and genetically related to international clones encoding transferable plasmid-mediated multidrug resistance.

• Samuelsen, Ørjan; Toleman, MA; Sundsfjord, Arnfinn; Rydberg, Johan; Leegaard, Truls Michael & Walder, M [Vis alle 12 forfattere av denne artikkelen] (2010). Molecular Epidemiology of Metallo-beta-Lactamase-Producing Pseudomonas aeruginosa Isolates from Norway and Sweden Shows Import of International Clones and Local Clonal Expansion. Antimicrobial Agents and Chemotherapy. ISSN 0066-4804. 54(1), s. 346–352. doi: 10.1128/AAC.00824-09.
• Leegaard, Truls M; Bootsma, Hester J; Caugant, Dominique A; Eleveld, Marc J; Mannsåker, Turid & Frøholm, Leif Oddvar [Vis alle 9 forfattere av denne artikkelen] (2010). Phenotypic and genomic characterization of pneumococcus-like streptococci isolated from HIV-seropositive patients. Microbiology (Reading). ISSN 1350-0872. 156(Pt 3), s. 838–848. doi: 10.1099/mic.0.035345-0.
• Dale, Einar; Heggelund, Lars; Samdal, Helvi Holm; Leegaard, Truls Michael; Edvardsen, Thor & Gjertsen, Erik (2010). Dramatisk sykehistorie forårsaket av uvanlig bakterie. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 130(2), s. 149–151. doi: 10.4045/tidsskr.08.0715.
• Leegaard, Truls Michael; Sandven, Per & Gaustad, Peter (2005). Clostridium tertium: 3 case reports. Scandinavian Journal of Infectious Diseases. ISSN 0036-5548. 37(3), s. 230–232.
• Heir, Even; Lindstedt, Bjørn-Arne; Leegaard, Truls Michael; Gjernes, Elisabet & Kapperud, Georg (2004). Incidence and characterization of integrons in blood culture and clinical gastrointestinal Escherichia coli in Norway and reporting of a novel class 1 integron-located lincodamide resistance gene. Annals of Clinical Microbiology and Antimicrobials. ISSN 1476-0711. 3(12).
• Sidhu, Maan Singh; Heir, Even; Leegaard, Truls Michael; Wiger, Karianne & Holck, Askild (2002). Frequency of disinfectant resistance genes and genetic linkage with beta-lactamase transposon Tn552 among clinical staphylococci. Antimicrobial Agents and Chemotherapy. ISSN 0066-4804. 46(9), s. 2797–2803. doi: 10.1128/AAC.46.9.2797-2803.2002. Vis sammendrag

  A total of 61 strains of Staphylococcus aureus and 177 coagulase-negative staphylococcal strains were isolated from the blood of patients with bloodstream infections and from the skin of both children under cancer treatment and human immunodeficiency virus-positive patients. The MIC analyses revealed that 118 isolates (50%) were resistant to quaternary ammonium compound-based disinfectant benzalkonium chloride (BC). The frequencies of resistance to a range of antibiotics were significantly higher among BC-resistant staphylococci than among BC-sensitive staphylococci. Of 78 BC-resistant staphylococcal isolates, plasmid DNA from 65 (83%), 2 (3%) 43 (55%) and 15 (19%) isolates hybridized to qacA or -B (qacA/B), qacC, blaZ, and tetK probes, respectively. The qacA/B and blaZ probes hybridized to the same plasmid in 19 (24%) staphylococcal strains. The plasmids harboring both qacA/B and blaZ genes varied from approximately 20 to 40 kb. The Staphylococcus epidermidis Fo162 isolate, harboring multiresistance plasmid pMS62, contained qacA/B and blaZ together with tetK. Molecular and genetic studies indicated different structural arrangements of blaZ and qacA/B, including variable intergenic distances and transcriptional directions of the two genes on the same plasmid within the strains. The different organizations may be due to the presence of various genetic elements involved in cointegration, recombination, and rearrangements. These results indicate that qac resistance genes are common and that linkage between resistance to disinfectants and penicillin resistance occurs frequently in clinical isolates in Norway. Moreover, the higher frequency of antibiotic resistance among BC-resistant strains indicates that the presence of either resistance determinant selects for the other during antimicrobial therapy and disinfection in hospitals.

• Alvseike, Ole; Leegaard, Truls Michael; Aavitsland, Preben & Lassen, Jørgen Fr (2002). Trend of multiple drug resistant Salmonella Typhimurium in Norway. Eurosurveillance. ISSN 1025-496X. 7, s. 5–7.
• Leegaard, Truls Michael; Caugant, Dominique A; Bruun, Johan N; Frøholm, Leif Oddvar; Sandven, Per & Høiby, Ernst Arne (2002). Do HIV-seropositive patients become colonised with resistant microorganisms? European Journal of Clinical Microbiology and Infectious Diseases. ISSN 0934-9723. 12, s. 856–863.

Se alle arbeider i Cristin

• Martínez, Miguel Julián; Cotten, Matthew; Phan, My V.T.; Becker, Karsten; Espasa, Mateu & Leegaard, Truls Michael [Vis alle 9 forfattere av denne artikkelen] (2023). Viral epidemic preparedness: a perspective from five clinical microbiology laboratories in Europe. Clinical Microbiology and Infection (CMI). ISSN 1198-743X. doi: 10.1016/j.cmi.2023.04.024. Fulltekst i vitenarkiv
• Ulvestad, Elling; Kommedal, Øyvind; Simonsen, Gunnar Skov; Müller, Fredrik; Leegaard, Truls Michael & Löhr, Iren Høyland [Vis alle 7 forfattere av denne artikkelen] (2020). Norges mikrobiologiske utbruddsberedskap er truet. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 140(11), s. 1096–1097. doi: 10.4045/tidsskr.20.0451.
• Müller, Fredrik; Leegaard, Truls Michael; Simonsen, Gunnar Skov; Løhr, Iren H; Nordbø, Svein Arne & Kommedal, Øyvind [Vis alle 7 forfattere av denne artikkelen] (2020). Nye signaler om koronatester. [Avis]. Aftenposten.
• Simonsen, Gunnar Skov; Nordbø, Svein Arne; Leegaard, Truls Michael; Ulvestad, Elling & Müller, Fredrik (2020). Svært viktig at fagmiljøer har fleksibilitet og ressurser til testing av koronavirus . [Avis]. Aftenposten.
• Bruun, Tone; Nakstad, Britt; Greve-Isdahl, Margrethe; Hovde, Heidi; Leegaard, Truls Michael & Flem, Elmira (2019). Premature barn bør tidlig vaksineres mot rotavirus. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 139(10). doi: 10.4045/tidsskr.19.0079.
• Berg, Are Stuwitz; Inchley, Christopher; Fjaerli, H.O.; Leegaard, Truls Michael & Nakstad, Britt (2016). Microbial aetiology of paediatric pneumonia complicated with parapneumonic effusion in the era of pneumococcal vaccination. Infectious Diseases. ISSN 2374-4235. 48(9), s. 712–714. doi: 10.1080/23744235.2016.1192721.
• Hansen, Mona; Myrvang, Ellen; Kraus Chrsitiansen, Irene; Molden, Tor; Eieland, Alexander Kirkeby & Meisal, Roger [Vis alle 13 forfattere av denne artikkelen] (2014). Human papillomavirus prevalence and genotype distribution in urine samples from non-vaccinated cohorts of 17 and 21 year old girls/women in Norway.
• Meisal, Roger; Rounge, Trine Ballestad; Molden, Tor; Worren, Merete Molton; Kraus Christiansen, Irene & Hovig, Eivind [Vis alle 8 forfattere av denne artikkelen] (2014). High throughput DNA sequencing for the detection and genotyping of human papillomavirus.
• Samuelsen, Ørjan; Naseer, Mohammed Umaer; Karah, Nabil; Lindemann, Paul Christoffer; Leegaard, Truls Michael & Sundsfjord, Arnfinn [Vis alle 7 forfattere av denne artikkelen] (2013). Identification of Enterobacteriaceae isolates with OXA-48 and coproduction of OXA-181 and NDM-1 in Norway. Journal of Antimicrobial Chemotherapy. ISSN 0305-7453. 68(7), s. 1682–1685. doi: 10.1093/jac/dkt058.
• Sandven, Per; Bergh, Kåre; Leegaard, Truls Michael & Steinbakk, Martin (2012). Diagnostikk ved fremmedlegeme-relaterte infeksjoner. Strategimøte nr 25, 2011. Nasjonalt folkehelseinstitutt. ISSN 978-82-8082-520-9. Fulltekst i vitenarkiv

Se alle arbeider i Cristin