Serologic evidence of avian influenza (H4N6) exposure in a wild-caught raccoon.

Growing concerns about avian influenza, and its effect on agriculture and human health, have highlighted the need to understand the role of wildlife in maintaining and spreading the virus. We surveyed the wildlife inhabiting a poultry farm with recent H3N6 and H4N6 avian influenza virus exposure in Pennsylvania, U.S.A. One raccoon (Procyon lotor) tested positive for H4N6 antibodies. This is the first recorded incident of avian influenza exposure in a wild raccoon. We suggest that raccoons may play a role in the transmission of avian influenza viruses and in compromising biosecurity efforts at poultry operations.