Challenging the conceptual framework of maintenance hosts for influenza A viruses in wild birds

1.The conceptual framework considering Anseriformes and Charadriiformes as the main maintenance hosts for influenza A viruses (IAV) in wild birds has shaped IAV research and surveillance over the last decades. 2.We challenge this framework by reviewing the worldwide surveillance data on non-Anseriformes and non-Charadriiformes (NANC) species, generally considered as playing little role in IAV maintenance, available in literature and online data bases (close to 200 sources). 3.Globally, we found an IAV infection rate of 1.51% (95% CI, 1.44%–1.59%) for c.101 000 birds tested from NANC species. If Anseriformes have, as expected, a higher infection rate than any other bird orders, eight bird orders have an infection rate higher or close to the Charadriiformes infection rate, challenging the status of Charadriiformes. 4.We interpret the attention paid in favour of Charadriiformes by an extrapolation bias from data collected in hotspots of IAV infection in Charadriiformes (e.g. Delaw...