Submitted to: Poultry Science Association
Publication Type: Proceedings
Publication Acceptance Date: 8/7/2008
Publication Date: 3/25/2009
Citation: Spackman, E. 2009. The ecology of avian influenza virus in wild birds: What does this mean for poultry? Poultry Science. 88:847-850.
Interpretive Summary: Wilds birds are the primary reservoir for avian influenza virus (AIV) and can serve as a source of virus for poultry. Understanding the ecology of the virus in its natural host systems can help to elucidate transmission to and within poultry. The ecology of AIV is comprised of the interaction of the host, virus and environment and is critical to understanding the maintenance and transmission of the virus. Data on the hosts, of which dabbling ducks and shorebirds seem to be the most important, and their habitat environment is limited and long term data on virus prevalence is only available for a few areas. However in recent years the depth of data has increased due to worldwide surveillance for the Asian H5N1 highly pathogenic AIV. Despite some unique biological properties of this virus lineage, data on this virus in wild birds and it’s transmission to poultry in some areas may give insight into the virus ecology in general. Observations from outbreaks of the Asian H5N1 in wild birds in poultry reinforce that out-door rearing of poultry is a major factor in the transmission of AIV from wild birds to domestic poultry.
Technical Abstract: As natural hosts for avian influenza virus (AIV), wild birds, particularly aquatic birds, are the primary reservoir for transmission of AIV to domestic poultry. Therefore understanding the dissemination and maintenance of AIV in wild birds is important for understanding the factors that contribute to transmission of AIV from wild birds to poultry. However, relatively little is known about the ecology of the virus in wild birds and the depth of data is inconsistent world-wide. Also, the biology of the virus itself is very important as AIV is a biologically and genetically diverse virus which is highly adaptable to different hosts and likely to the environment as well. Some insight may be gained from the Asian H5N1 highly pathogenic (HP) AIV which was first reported in 1997. Because of its wide geographic distribution and its impact on human and animal health, surveillance for this virus has increased considerably in wild birds worldwide since 2005. Also, numerous species which have not previously been represented in AIV testing have been included in surveillance for the Asian H5N1 HPAIV allowing for a more complete understanding of the distribution of AIV in wild birds.