title: Transmission of influenza on international flights, may 2009.
abstract: Understanding the dynamics of influenza transmission on international flights is necessary for prioritizing public health response to pandemic incursions. A retrospective cohort study to ascertain in-flight transmission of pandemic (H1N1) 2009 and influenza-like illness (ILI) was undertaken for 2 long-haul flights entering Australia during May 2009. Combined results, including survey responses from 319 (43%) of 738 passengers, showed that 13 (2%) had an ILI in flight and an ILI developed in 32 (5%) passengers during the first week post arrival. Passengers were at 3.6% increased risk of contracting pandemic (H1N1) 2009 if they sat in the same row as or within 2 rows of persons who were symptomatic preflight. A closer exposed zone (2 seats in front, 2 seats behind, and 2 seats either side) increased the risk for postflight disease to 7.7%. Efficiency of contact tracing without compromising the effectiveness of the public health intervention might be improved by limiting the exposed zone.
authors.affiliation: Department of Health and Ageing, Canberra, Australian Capital Territory, Australia.
authors.forename: A Ruth
authors.initials: AR
authors.lastname: Foxwell
authors.forename: Leslee
authors.initials: L
authors.lastname: Roberts
authors.forename: Kamalini
authors.initials: K
authors.lastname: Lokuge
authors.forename: Paul M
authors.initials: PM
authors.lastname: Kelly
mesh_terms: D000401:Aircraft; D001315:Australia; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D058873:Pandemics / Q000517:prevention & control; D011634:Public Health; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons; D011795:Surveys and Questionnaires; D013997:Time Factors; D014195:Travel