AIV molecular detection
A total of 875 biological samples of wild ducks (n=597), poultry (n=103), and swine (n=175) were collected from November 2016 to May 2017 (Figure 2). Eight dabbling duck species and two diving duck species were sampled for IAV detection by qRT-PCR in the Lerma marshes, State of Mexico. Twenty-two wild dabbling ducks (3.68%) tested positive for IAV (Table 1). The IAV positive samples were obtained from November to February, predominantly in the mid-winter season. The IAV positive wild dabbling ducks belonged to four species: Green-winged Teal (Anas crecca ), Blue-winged Teal (Spatula discors ), Northern Shoveler (Spatula clypeata ) and Mexican duck (Anas diazi ) (Figure 3). Blue-winged Teal was the most frequent species in the sampling area, followed by Green-winged Teal. The highest IAV frequency was found in Mexican duck, followed by Northern Shoveler (Table 1). All swabs from wild diving ducks, pigs, and poultry tested negative for IAV by qRT-PCR.