Fighting Avian Flu: An evaluation of tools that improve the prediction and detection of outbreaks in poultry farms

Outbreaks of avian influenza are a major concern for the poultry industry, as well as for society. It is therefore important to prevent outbreaks as much as possible, and to detect outbreaks at an early stage when they do occur to prevent between-farm spread. Several tools were evaluated to predict avian influenza outbreaks. Avian influenza is transmitted to poultry via contact with feces of infected wild birds. The community of bacteria in the feces of laying chickens was studied for clues that can be related to contact with feces of wild birds. Also, it was investigated whether the administration of wild bird feces to layers resulted in changes in the community of bacteria in layers’ feces. No indications were found that the bacterial composition of feces of layers could be used to quantify contact with wild birds. Rather, the bacterial community in healthy, adult layers was stable and not easily perturbed. In parallel, wild waterfowl densities were used to generate a map of avian influenza outbreak risk across the Netherlands. This risk map identified high risk areas and identified wild bird species that are possibly important contributors to this outbreak risk. It was also shown that a relative increase in mortality in poultry, preferably combined with the observation of clinical signs, could successfully be used for early detection of avian influenza outbreaks in different types of poultry farms. The described methods and results give direction for future research into improving the prediction and prevention of avian influenza.