FIG 4 .

(a) Exposure to wild avian species is not associated with enriched HA-specific antibody titers. Endpoint ELISA titers were determined for avian H4, H5, H6, H8, and H12 and human H7 hemagglutinin antigens. (b) Contact with poultry is associated with increased levels of anti-H7 antibodies. Endpoint ELISA titers were determined for avian H4, H5, H6, H8, and H12 and human H7 hemagglutinin antigens. Whiskers of box plots represent 10th and 90th percentiles, and the horizontal line and plus sign in each box give the median and mean titers of individuals, respectively. Variability in titer is shown by plotting the first and third quartiles of the titers as the outer limits of the box. Points beyond the whiskers denote outliers. Box color represents the participant-reported avian species exposure (white, passerines; gray, waterfowl; red, shorebirds; blue, raptors). Groups were compared by two-tailed, unpaired t test, and false discovery rate-adjusted P values were determined.