title: Timing of influenza A(H5N1) in poultry and humans and seasonal influenza activity worldwide, 2004-2013.
abstract: Co-circulation of influenza A(H5N1) and seasonal influenza viruses among humans and animals could lead to co-infections, reassortment, and emergence of novel viruses with pandemic potential. We assessed the timing of subtype H5N1 outbreaks among poultry, human H5N1 cases, and human seasonal influenza in 8 countries that reported 97% of all human H5N1 cases and 90% of all poultry H5N1 outbreaks. In these countries, most outbreaks among poultry (7,001/11,331, 62%) and half of human cases (313/625, 50%) occurred during January-March. Human H5N1 cases occurred in 167 (45%) of 372 months during which outbreaks among poultry occurred, compared with 59 (10%) of 574 months that had no outbreaks among poultry. Human H5N1 cases also occurred in 59 (22%) of 267 months during seasonal influenza periods. To reduce risk for co-infection, surveillance and control of H5N1 should be enhanced during January-March, when H5N1 outbreaks typically occur and overlap with seasonal influenza virus circulation.
authors.forename: Lizette O
authors.initials: LO
authors.lastname: Durand
authors.forename: Patrick
authors.initials: P
authors.lastname: Glew
authors.forename: Diane
authors.initials: D
authors.lastname: Gross
authors.forename: Matthew
authors.initials: M
authors.lastname: Kasper
authors.forename: Susan
authors.initials: S
authors.lastname: Trock
authors.forename: Inkyu K
authors.initials: IK
authors.lastname: Kim
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Bresee
authors.forename: Ruben
authors.initials: R
authors.lastname: Donis
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Uyeki
authors.forename: Marc-Alain
authors.initials: MA
authors.lastname: Widdowson
authors.forename: Eduardo
authors.initials: E
authors.lastname: Azziz-Baumgartner
mesh_terms: D000818:Animals; D004196:Disease Outbreaks; D062306:Geography, Medical; D014943:Global Health; D049674:History, 21st Century; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype; D005585:Influenza in Birds / Q000453:epidemiology* / Q000266:history / Q000821:virology; D007251:Influenza, Human / Q000453:epidemiology* / Q000266:history / Q000821:virology; D011200:Poultry; D012621:Seasons; D013997:Time Factors