Researchers at the University of Georgia have created a model which takes into account both direct and indirect transmission of the H5N1 influenza virus in birds.
The model was inspired from the data on the persistence of avian influenza viruses in the environment, contrary to the earlier models which only considered direct transmission of the virus.
Pejman Rohani, lead author of the study and a professor in the UGA Odum School of Ecology, said research has revealed that some viruses can persist in water for up to 150 days. In such a case, models taking into account direct transmission would conclude there is no risk of an outbreak as no infected birds are present.
The new model also takes into account variables such as the size of the water body and the rate at which infected birds recover. It has been published in the online edition of Proceedings of the National Academy of Sciences.
Lead author of another study published in Veterinary Microbiology, Justin Brown, said the role of environment in the transmission of avian flu has been undefined, and that migration and factors related to the biology of the avian host are important factors that drive the epidemiology of the flu.