A national study of US bird banders for evidence of avian influenza virus infections

BackgroundPreviously we have found that Midwestern US wildlife biologists, poultry farmers, veterinarians, and duck hunters have had evidence of avian influenza virus infections (AIVs).ObjectivesWe sought to evaluate a national sample of US bird banders for previous evidence of AIV infection.Study designControlled, cross-sectional serological survey.ResultsIn 2009 and 2010 we enrolled 157 registered bird banders from 40 US states and compared their enrollment data and serological results with 78 adult age-group matched controls from Iowa. On average, the bird banders had 15 years of wild bird exposure, banded 20 days per year, worked chiefly in 1 of the 4 North American flyways, and banded 300 individual birds of 5 different species per season. While handling birds, only 15% of banders reported wearing gloves. Three bird banders and 1 control had evidence of previous infection (1 AIV each) with A/BWTE/Ohio/07/495762-6(H7N3), A/Ty/MN/38391-6/95(H9N2) or A/CK/NJ/7290-2/95(H11N3) by microneutralization assay. There was no evidence of previous infection with a representative sample of H4, H5, H6, H8, or H10 AIVs. Participants were followed for influenza-like-illness for a median of 7 months and 4 (3 bird banders) submitted self-collected eye, nasal, and throat influenza-like-illness swab specimens, 1 of which collected in November of 2009, yielded a pandemic H1N1 influenza A virus.ConclusionDespite reports of conjunctivitis and upper respiratory symptoms while bird banding, we found sparse evidence that US bird banders had infections with AIVs.