Virus load in shared water pans for birds in an interspecies study of influenza A(H7N9) virus transmission. A shared drinking water sample (500-μL) was collected daily on postinoculation days 1–4 and 8. Virus titers in samples were determined in embryonated chicken eggs. A) Shedding from A/Anhui/1/2013 (H7N9)–infected birds. B) Shedding from A/Chicken/Rizhao/867/2013 (H7N9)–infected birds. Cages 1 and 2 indicate results from duplicate experimental groups. EID50, 50% egg infectious dose; Ck, chicken; Fn, finch; QI, quail.