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Lessler J, Reich NG, Cummings DA; New York City Department of Health and Mental Hygiene Swine Influenza Investigation Team; Nair HP, Jordan HT, Thompson N.Lessler J, et al.N Engl J Med. 2009 Dec 31;361(27):2628-36. doi: 10.1056/NEJMoa0906089.N Engl J Med. 2009.PMID: 20042754Free article.