Failure of chickens to act as sentinels during an epizootic of eastern equine encephalitis in southern New Jersey, USA

A series of 10 chicken flocks placed in areas of southern New Jersey, USA, preceding an epizootic of eastern equine encephalitis (EEE) virus failed to function adequately as sentinels for the outbreak. Epidemiological data including virus isolations from mosquitoes and wild birds, confirmation of equine deaths due to EEE virus, and a confirmed human case showed that most of the chickens placed in areas where virus was known to be present did not develop antibody of EEE. Those chickens that did develop antibody seroconverted late in the epizootic period. Data suggest that chickens do not function as a warning mechanism of EEE virus but merely act as an added indicator of virus activity.