4Trifonov V, Khiabanian H, Rabadan R. Geographic dependence, sur- veillance, and origins of the 2009 influenza A ( H1 N1 ) virus [J].N EnglJ Med, 2009, 361 (2): 115-119.
5ANZIC Influenza Investigators. Critical care services and 2009 HI N1 in- fluenza in Australia and New Zealand [J]. N Engl J Med, 2009, 361 (20): 1925-1934.
6Louie JK, Aeosta M, Wilher K, et al. Factors associated with death or hospitalization due to Pandemic 2009 influenza A ( H1N1 ) infection in Califonia [J]. JAMA, 2009, 302 (17): 1896-1902.
7Van Kerkhove MD, Vandemaele KAH, Shinde V, et al. Risk factors for severe outcomes following 2009 Influenza A ( H1N1 ) infection: A dobal oooled analysis[J]. PLoS Med. 2011, 8 (7): e1001053.
8Echevarria Zuno S, Mejia - Arangur JM, Mar - Obeso AJ, et al. Infection and death from influenza A H1NI virus in Mexico: A ret- rospective analysis [ J ]. Lancet, 2009, 374 (9707) : 2072 - 2079.
9Higuera Iglesias AL, Kudo K, Manabe T, et al. Reducing occurrence and severity of pneumonia due to pandemic HI N1 2009 by early oselta- mivir administration: A retrospective study in Mexico [ J ]. PLoS ONE, 2011, 6 (7): e21838.
