Mean H4N6 AIV RNA detected using 3 different sampling methods.

<p>AIV RNA quantities detected in cloacal swabs, oropharyngeal swabs, and fecal samples were compared. Because fecal samples were originally weighed (not swabs), we determined that an average fecal swab contained 0.0929±0.0089 g of feces and present these data as ‘fecal swab equivalents.’ Estimated virus concentrations in fecal swab equivalents were higher than the concentrations detected in cloacal and oropharyngeal swabs regardless of the age of ducks or route of infection. Error bars represent standard errors.