Public Defence: Magnus Nygård Osnes

MSc Magnus Nygård Osnes at Institute of Basic Medical Sciences will be defending the thesis “Genome epidemiology of Neisseria gonorrhoeae and SARS-CoV-2 - Strain dynamics from the level of individuals to global dissemination” for the degree of PhD (Philosophiae Doctor).

Image may contain: Top, Forehead, Hair, Face, Head.

Photo: Katinka Lund Bergskaug. 

An electronic copy of the thesis may be ordered from the faculty up to 2 days prior to the public defence. Inquiries regarding the thesis after the public defence must be addressed to the candidate.

Trial Lecture – time and place

See Trial Lecture.

Adjudication committee

  • First opponent: Professor Edward J. Feil, University of Bath
  • Second opponent: Associate Professor Nicole Wheeler, University of Birmingham
  • Third member and chair of the evaluation committee: Professor Fredrik Müller, University of Oslo

Chair of the Defence

Professor Tone Tønjum, University of Oslo

Principal Supervisor

Senior researcher Vegard Eldholm, Norwegian Institute of Public Health


Whole-genome sequencing technology is rapidly advancing, and genomic data is now a pivotal aid for public health agencies tracking disease outbreaks. Genomic data allows us to better understand the epidemiology, evolution, population dynamics and spread of pathogens. The field that describes the interplay between the factors mentioned above is known as phylodynamics. In this work, Osnes et al. develop and applies phylodynamic methods to the bacterium Neisseria gonorrhoeae and the virus SARS-CoV-2. 

A significant challenge with N. gonorrhoeae is that it rapidly develops resistance to all available drugs for treatment. The authors collect large genomic datasets on two important lineages of N. gonorrhoeae. They estimate the ancestry of the samples and describe evolutionary events that have led to antibiotic resistance. From the ancestral trees, they describe geographical transmission dynamics and show that Asia plays a central role in the emergence of antibiotic-resistant N. gonorrhoeae. Additionally, they use genome-based transmission analysis to investigate the relative role of different infection sites in the transmission of the disease. 

The SARS-CoV-2 pandemic has caused significant mortality from 2020 to 2022. One of the greatest challenges under the pandemic has been the emergence of new variants of the virus that has led to multiple epidemic waves. Osnes et al. analyze an extensive genome collection representing the second wave of infections in Norway from autumn 2020 to spring 2021. Over this period, the alpha variant arrived in Norway and quickly replaced older lineages in circulation. The authors estimate the arrival time of the alpha variant in Norway, the number of imports represented in the data, and the number of Norwegian sequences that can be attributed to each importation. They show that a small number of imports explain a high proportion of local transmissions. To perform the analyses, the authors develop an open-source R programming package.

Additional information

Contact the research support staff.

Published Apr. 19, 2022 10:41 AM - Last modified May 2, 2022 1:44 PM