title: Historical perspective--Emergence of influenza A (H1N1) viruses.
authors: School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
authors: Shanta M
authors: SM
authors: Zimmer
authors: Donald S
authors: DS
authors: Burke
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D000918:Antibody Specificity; D000940:Antigenic Variation; D001717:Birds; D021821:Communicable Diseases, Emerging / Q000266:history* / Q000635:transmission / Q000821:virology; D004196:Disease Outbreaks / Q000266:history; D019143:Evolution, Molecular; D016679:Genome, Viral; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000276:immunology; D053121:Influenza A Virus, H2N2 Subtype / Q000235:genetics; D007251:Influenza, Human / Q000266:history* / Q000821:virology; D009976:Orthomyxoviridae Infections / Q000266:history* / Q000635:transmission / Q000662:veterinary / Q000821:virology; D016865:Reassortant Viruses / Q000235:genetics*; D013552:Swine; D015047:Zoonoses / Q000266:history* / Q000635:transmission / Q000821:virology
chemical_list: D000914:Antibodies, Viral