Epidemiology of avian influenza in Vietnam – the role of ducks and survival of virus in water
The broad objective was to study the epidemiology of avian influenza (AI) in Vietnam – following the ongoing outbreak of AI in many provinces of the country. The project primarily focused on the role of ducks as a reservoir for the AI virus and the possible effects that persistence of the virus in duck populations may have. It has been clearly demonstrated that ducks under vietnamese conditions can be infected with AIV and that they can shed virus for longer periods of time without showing any clinical signs. A MSc project performed in 2004 by Do Quy Phuong which is suggested to be the Ph.D student of the present project documented that 80 % of the ducks are positive for H5 antibodies. However, it is not clear in which way passage in ducks may affect the virulence of the virus just as the significance of the passage for other important aspects such as host-adaptation is unclear. The second major epidemiological aspect which will be investigated concerns the ability of the virus to survive in the aquatic environment which is of major importance under vietnamese conditions. Outcomes: The PhD project will be defended autumn 2011.