Assessment of the viral fitness of Highly Pathogenic H5 avian influenza viruses using in vitro, ex vivo and in vivo models

Summary

Highly pathogenic avian influenza (HPAI) H5N1 poses a major threat to both animal health and public health. This thesis examines the viral fitness of HPAI viruses in avian and mammalian species, combining innovative in vitro and ex vivo models with traditional animal studies.
We highlight key differences in HPAI viral fitness across multiple species, including chickens, ducks, barnacle geese, eurasian wigeons, red foxes, cows, and ferrets. Additionally, a framework is presented to translate in vitro viral fitness to in vivo measured viral fitness.
The research in this thesis highlights the importance of more extensive comparisons between in vitro and in vivo studies to improve risk assessment of emerging HPAI viruses in both avian and mammalian species.