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Epizootic deaths from West Nile virus infection were observed in American crows, suggesting lateral transmission in a cold season.
In New York, an epizootic of American crow (Corvus brachyrhynchos) deaths from West Nile virus (WNV) infection occurred during winter 2004-2005, a cold season when mosquitoes are not active. Detection of WNV in feces collected at the roost suggests lateral transmission through contact or fecal contamination.
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Dawson et al. (2007) studied this question.
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