Øystein Evensen is head of the research group "Host-pathogen interactions in infection and immunity" at the Faculty of Veterinary Medicine. He got his degree in veterinary medicine from the Norwegian School of Veterinary Science in 1984 and his PhD in pathology from the same institution in 1987.

He worked for more than 10 years after his PhD as post-doc and research scientist at the Norwegian Veterinary Institute in Oslo, Norway, more than 7 years in pharmaceutical industry - Alpharma - (1995-2002), later to become PHARMAQ, with development of vaccines for finfish, particularly salmon. Over the last 19 years he has been full professor at the Norwegian University of Life Sciences, Faculty of Veterinary Medicine, where he heads a research group of more than 15 people, that includes 2 associate professors, several research scientists, post docs and PhD students. The research groups is focusing on viral and bacterial diseases of farmed salmon, mechanisms of infection and vaccine development. The work is funded through projects from the Research Council of Norway (Havbruk and FriPro), the EU Framework program and pharmaceutical industry. Main research focus over the last years has been cardiomyopathy syndrome of Atlantic salmon, and the research group was the first to describe the cause of the disease, piscine myocarditis virus. The group has ongoing research programs on pancreas disease virus, and Evensen's groups also work on developing vaccines against sea lice infection/infestation in Atlantic salmon, with financial support from FHF (Seafood Research Fund). 

The research group is heavily involved in research and capacity building in Africa (Zambia, Tanzania, Kenya, Uganda, Malawi, Mozambique, Nigeria and Ghana) through two NORHED-II (NORAD)-funded research programmes, focusing on capacity building and training of young research scientists in the south in fish health and environmental health. Through this involvement, there has been a lot of focus on tilapia lake virus, diagnostic methods and pathogenesis studies. 

The research group also uses model fish, zebrafish, for study of infection mechanisms and pathogenic events of disease (pathogenesis) related mainly to viral infections. Here the group has used reverse genetics made viruses to understand virulence mechanisms and virulence factors that the virus employ to circumvent antiviral responses of the host. 

Publications are found here