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Phylogenetic, seroarcheological, and epidemiological evidence indicates those born earlier or later than \u223c1880\u20131900 would have had some protection against the 1918 H1N1 virus, whereas many young adults born from \u223c1880\u20131900 may have lacked such protection because of childhood exposure to an antigenically distinct H3N8 virus. Our findings suggest that better understanding of how initial exposure shapes lifetime immunity may enhance the prediction and control of future IAV pandemics and seasonal epidemics.<\/jats:p>","DOI":"10.1073\/pnas.1324197111","type":"journal-article","created":{"date-parts":[[2014,4,29]],"date-time":"2014-04-29T03:37:37Z","timestamp":1398742657000},"page":"8107-8112","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":247,"title":["Genesis and pathogenesis of the 1918 pandemic H1N1 influenza A virus"],"prefix":"10.1073","volume":"111","author":[{"given":"Michael","family":"Worobey","sequence":"first","affiliation":[{"name":"Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guan-Zhu","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Rambaut","sequence":"additional","affiliation":[{"name":"Institute of Evolutionary Biology and"},{"name":"Centre for Infection, Immunity, and Evolution, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom; and"},{"name":"Fogarty International Center, National Institutes of Health, Bethesda, MD 20892"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2014,4,28]]},"reference":[{"key":"e_1_3_3_1_2","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1919.02610310007003"},{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.3201\/eid1201.050979"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.3201\/eid1802.111409"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1086\/511989"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1086\/322662"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1086\/591708"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1111179108"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1038\/nature04825"},{"key":"e_1_3_3_9_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0904991106"},{"key":"e_1_3_3_10_2","doi-asserted-by":"publisher","DOI":"10.1038\/nature13016"},{"key":"e_1_3_3_11_2","doi-asserted-by":"publisher","DOI":"10.1093\/oxfordjournals.aje.a121543"},{"key":"e_1_3_3_12_2","volume-title":"Pandemic Influenza, 1700-1900: A Study in Historical Epidemiology","author":"Patterson KD","year":"1986","unstructured":"KD Patterson Pandemic Influenza, 1700-1900: A Study in Historical Epidemiology (Rowan & Littlefield, Totowa, NJ, 1986)."},{"key":"e_1_3_3_13_2","first-page":"453","article-title":"Interpretations of influenza antibody patterns of man","volume":"41","author":"Davenport FM","year":"1969","unstructured":"FM Davenport, E Minuse, AV Hennessy, T Francis, Interpretations of influenza antibody patterns of man. 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