The discovery in 1976 of waterfowl as the primary reservoir of influenza A viruses (IAV) has since spurred decades of waterfowl surveillance efforts by researchers dedicated to understanding the ecology of IAV and its subsequent threat to human and animal health. Here, we employed a multi-decade, continental-scale approach of surveillance data to understand trends of seasonal IAV subtype diversity. Between 1976-2015, IAVs were detected in 8,427 (10.8%) of 77,969 samples from migratory waterfowl throughout the Central and Mississippi Migratory Flyways in the United States and Canada. A total of 96 hemagglutinin (HA)/neuraminidase (NA) subtype combinations were isolated, which included most HA (H1-H14) and all 9 NA subtypes. We observed an annual trend of high influenza prevalence, involving a few dominant subtypes, on northern breeding grounds during summer with progressively lowered influenza prevalence, comprised of a highly diverse profile of subtypes, as waterfowl migrate towards southern wintering grounds. Isolates recovered during winter had the highest proportion of mixed and rare HA/NA combinations, indicating increased opportunity for reassortment of IAVs. In addition, 70% of H5 and 49% of H7 IAV isolates were recovered from samples collected during fall and spring respectively; these are subtypes that can have significant implications for public health and agriculture sectors. Annual cyclical dominance of subtypes on northern breeding grounds are revealed through the longitudinal nature of this study. Our novel findings exhibit the unrealized potential for discovery using existing IAV surveillance data.Wild aquatic birds are the primary natural reservoir of influenza A viruses (IAV) and are therefore responsible for the dispersal and maintenance of IAV representing a broad range of antigenic and genetic diversity. The aims of IAV surveillance in waterfowl not only relate to understanding the risk of spillover risk to humans but also to improving our understanding basic questions related to IAV evolution and ecology. By evaluating several decades of surveillance data from wild aquatic birds sampled along North American migratory flyways, we discovered an annual trend of increasing subtype diversity during southbound migration, peaking on southern wintering grounds. Winter sampling revealed the highest proportion of mixed and rare infections which suggest higher opportunity for spillover. These findings allow improvements to surveillance efforts to robustly capture IAV diversity that will be used for vaccine development and cultivate a more thorough understanding of IAV evolution and persistence mechanisms.Copyright © 2020 American Society for Microbiology.
Voluntary wheel running improves outcomes in an early life stress-induced model of urologic chronic pelvic pain syndrome in male mice.
January 7, 2021
Oxidative stress parameters and antioxidants in patients with bipolar disorder: Results from a meta-analysis comparing patients, including stratification by polarity and euthymic status, with healthy controls.
August 13, 2020
Associations of fluoride exposure with sex steroid hormones among U.S. children and adolescents, NHANES 2013-2016.
January 30, 2020
March 13, 2012
- ACC 2020The American College of Cardiology decided to cancel ACC.20/WCC due to COVID-19, which was scheduled to take place March 28-30 in Chicago. However, ACC.20/WCC Virtual Meeting continues to release cutting edge science and practice changing updates for cardiovascular professionals on demand and free through June 2020.
- ENDO: 2020ENDO 2020 Annual Conference has been canceled due to COVID-19. Here are highlights of emerging data that has still been released. Keep an eye out for ENDO Online 2020, which will take place from June 8 to 22.