ECOFLU : Understanding the ecology of Highly Pathogenic Avian Influenza in wild bird populations

Wildlife populations naturally experience a wide range of infections and disease. Understanding how they circulate in the environment, how they are evolving over time and how different hosts are affected is key to understanding both their impact on different animal species and their potential to spill-over into domesticated animals and humans. We are currently experiencing a major outbreak of Avian Influenza that is having a major impact both on wild birds and commercial poultry at a global scale. This is a disease caused by infection by a group of Influenza A type viruses of which water birds are the natural host. These viruses usually circulate in wild waterfowl and shorebirds with relatively little impact. However, the past year has seen a significant change in the impact of one particular subtype of avian influenza called H5N1. Mortality reports in wild birds have been highest in seabirds with over 200,000 dead birds reported over a three month period in Scotland alone. These are novel hosts that up until this point have been relatively unaffected so we currently lack information about how this disease is impacting in these novel host populations, hindering our ability to make informed decisions about any potential mitigation strategies that might be put in place or evaluate their likely success.

In this project we have three main objectives. Firstly, we will track the evolution of the virus over time and space across a range of different host species. This will tell us about possible routes of transmission but also help us track how the virus is changing as it evolves and to identify any viral changes that may alter its pathogenicity or its ability to jump between species. Secondly, we will focus on the hosts and explore what proportion of birds are exposed and survive infection. We will do this in populations that have been monitored over many years so their individual life-histories, age, and migration routes are known to help us identify which whether particular parts of the population may be more vulnerable or more important in transmission. Finally we will use the data we are collecting to create a modelling framework that represents the wider population of different species to test how resilient different populations might be to this disease and to use as a tool to evaluate and prioritize potential mitigations that can be put in place to minimise any impact on host populations and limit future disease spread.