A High Diversity of Eurasian Lineage Low Pathogenicity Avian Influenza A Viruses Circulate among Wild Birds Sampled in Egypt
Open Access
- 12 July 2013
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 8 (7), e68522
- https://doi.org/10.1371/journal.pone.0068522
Abstract
Surveillance for influenza A viruses in wild birds has increased substantially as part of efforts to control the global movement of highly pathogenic avian influenza A (H5N1) virus. Studies conducted in Egypt from 2003 to 2007 to monitor birds for H5N1 identified multiple subtypes of low pathogenicity avian influenza A viruses isolated primarily from migratory waterfowl collected in the Nile Delta. Phylogenetic analysis of 28 viral genomes was performed to estimate their nearest ancestors and identify possible reassortants. Migratory flyway patterns were included in the analysis to assess gene flow between overlapping flyways. Overall, the viruses were most closely related to Eurasian, African and/or Central Asian lineage low pathogenicity viruses and belonged to 15 different subtypes. A subset of the internal genes seemed to originate from specific flyways (Black Sea-Mediterranean, East African-West Asian). The remaining genes were derived from a mixture of viruses broadly distributed across as many as 4 different flyways suggesting the importance of the Nile Delta for virus dispersal. Molecular clock date estimates suggested that the time to the nearest common ancestor of all viruses analyzed ranged from 5 to 10 years, indicating frequent genetic exchange with viruses sampled elsewhere. The intersection of multiple migratory bird flyways and the resulting diversity of influenza virus gene lineages in the Nile Delta create conditions favoring reassortment, as evident from the gene constellations identified by this study. In conclusion, we present for the first time a comprehensive phylogenetic analysis of full genome sequences from low pathogenic avian influenza viruses circulating in Egypt, underscoring the significance of the region for viral reassortment and the potential emergence of novel avian influenza A viruses, as well as representing a highly diverse influenza A virus gene pool that merits continued monitoring.Keywords
This publication has 52 references indexed in Scilit:
- Understanding the ecological drivers of avian influenza virus infection in wildfowl: a continental-scale study across AfricaProceedings Of The Royal Society B-Biological Sciences, 2011
- Long-distance migrating species of birds travel in larger groupsBiology Letters, 2011
- The development and genetic diversity of H5N1 influenza virus in China, 1996–2006Virology, 2008
- BEAST: Bayesian evolutionary analysis by sampling treesBMC Evolutionary Biology, 2007
- Persistent Host Markers in Pandemic and H5N1 Influenza VirusesJournal of Virology, 2007
- Multiple Anti-Interferon Actions of the Influenza A Virus NS1 ProteinJournal of Virology, 2007
- Spatial, Temporal, and Species Variation in Prevalence of Influenza A Viruses in Wild Migratory BirdsPLoS Pathogens, 2007
- NS1 Proteins of Avian Influenza A Viruses Can Act as Antagonists of the Human Alpha/Beta Interferon ResponseJournal of Virology, 2007
- The CPSF30 Binding Site on the NS1A Protein of Influenza A Virus Is a Potential Antiviral TargetJournal of Virology, 2006
- MUSCLE: multiple sequence alignment with high accuracy and high throughputNucleic Acids Research, 2004