Date of this Version
PNAS, October 25, 2016, vol. 113, no. 43, E6551–E6552
Krauss et al. (1) use lack of detection of highly pathogenic (HP) H5 clade 18.104.22.168 (henceforth “H5”) influenza A viruses (IAVs) from >22,000 wild bird samples collected in North America in 2014–2015 to argue that HP H5 IAVs disappeared from waterfowl and that unresolved mechanisms restrict emergence and perpetuation of HP IAVs in natural reservoir species. Here we offer an alternative interpretation.