Influenza A Virus Surveillance in Waterfowl in Missouri, USA, 2005–2013

Abstract

Missouri, United States, is located within the Mississippi Migratory Bird Flyway where wild waterfowl stop to feed and rest during migration and, weather permitting, to overwinter. Historically, Missouri has experienced sporadic influenza A virus (IAV) outbreaks in poultry and commercial swine. The introduction of IAVs from wild, migratory waterfowl is one possible source for the IAV, IAV genomic segments, or both involved in these outbreaks in key agricultural species. During 2005 through 2013, 3984 cloacal swabs were collected from hunter-harvested waterfowl in Missouri as part of an active IAV surveillance effort. Twenty-four avian species were represented in the sample population and 108 (2.7%) of the samples tested positive for IAV recovery. These IAV isolates represented 12 HA and nine NA subtypes and at least 27 distinct HA-NA combinations. An H14 IAV isolate recovered in Missouri during the sample period provided evidence for further establishment of the H14 subtype in North American wild waterfowl and gave proof that the previously rare subtype is more genetically diverse than previously detected. The present surveillance effort also produced IAV isolates that were genomically linked to the highly pathogenic H7N3 IAV strain that emerged in 2012 and caused severe disease in Mexico's domestic poultry. The presence of antigenically diverse IAV's circulating in wild waterfowl in the vicinity of commercial poultry and swine, along with the association of several wild-bird-lineage IAV genomic segments in viruses infecting poultry in North America, justifies continued attention to biosecurity efforts in food animal production systems and ongoing active IAV surveillance in wild birds.

Subtype Diversity of Influenza A Virus in North American Waterfowl: a Multidecade Study

“…Cloacal swabs, oropharyngeal swabs, tracheal swabs, and tissue samples were collected from birds at 295 study sites. Birds were trapped by standard live-capture methods or hunter harvested (45,46). Surveillance efforts were linked with bird-banding efforts on breeding and staging grounds in summer and in wintering areas during spring migration.…”

Blue-Winged Teals in Guatemala and Their Potential Role in the Ecology of H14 Subtype Influenza a Viruses

“…Four H14 sequences from Eurasia were subsequently made available in the public databases Bacterial and Viral Bioinformatics Resource Center (BV-BRC) and Global Initiative on Sharing Avian Influenza Data (GISAID), accessed on 8 July 2022, including samples from 1 garganey duck in Ukraine in 2006, 1 goose in Pakistan in 2014, and 1 sandpiper and 1 common teal in Russia in 2019. In North America, 16 additional H14 FLUAVs were detected sporadically in the period 2010–2018 from different species of dabbling ducks such as blue-winged-teal, northern-shoveler, long-tailed-duck, mallards, and scoter within the Pacific, Central, and Mississippi flyways [ 8 , 10 , 11 , 12 ].…”