title: Use of antiviral drugs to reduce household transmission of pandemic (H1N1) 2009, United Kingdom.
abstract: The United Kingdom implemented a containment strategy for pandemic (H1N1) 2009 through administering antiviral agents (AVs) to patients and their close contacts. This observational household cohort study describes the effect of AVs on household transmission. We followed 285 confirmed primary cases in 259 households with 761 contacts. At 2 weeks, the confirmed secondary attack rate (SAR) was 8.1% (62/761) and significantly higher in persons <16 years of age than in those >50 years of age (18.9% vs. 1.2%, p<0.001). Early (<48 hours) treatment of primary case-patients reduced SAR (4.5% vs. 10.6%, p = 0.003). The SAR in child contacts was 33.3% (10/30) when the primary contact was a woman and 2.9% (1/34) when the primary contact was a man (p = 0.010). Of 53 confirmed secondary case-patients, 45 had not received AV prophylaxis. The effectiveness of AV prophylaxis in preventing infection was 92%.
authors.affiliation: Health Protection Agency, London, UK. richard.pebody@hpa.org.uk
authors.forename: Richard G
authors.initials: RG
authors.lastname: Pebody
authors.forename: Ross
authors.initials: R
authors.lastname: Harris
authors.forename: George
authors.initials: G
authors.lastname: Kafatos
authors.forename: Mary
authors.initials: M
authors.lastname: Chamberland
authors.forename: Colin
authors.initials: C
authors.lastname: Campbell
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Nguyen-Van-Tam
authors.forename: Estelle
authors.initials: E
authors.lastname: McLean
authors.forename: Nick
authors.initials: N
authors.lastname: Andrews
authors.forename: Peter J
authors.initials: PJ
authors.lastname: White
authors.forename: Edward
authors.initials: E
authors.lastname: Wynne-Evans
authors.forename: Jon
authors.initials: J
authors.lastname: Green
authors.forename: Joanna
authors.initials: J
authors.lastname: Ellis
authors.forename: Tim
authors.initials: T
authors.lastname: Wreghitt
authors.forename: Sam
authors.initials: S
authors.lastname: Bracebridge
authors.forename: Chikwe
authors.initials: C
authors.lastname: Ihekweazu
authors.forename: Isabel
authors.initials: I
authors.lastname: Oliver
authors.forename: Gillian
authors.initials: G
authors.lastname: Smith
authors.forename: Colin
authors.initials: C
authors.lastname: Hawkins
authors.forename: Roland
authors.initials: R
authors.lastname: Salmon
authors.forename: Bryan
authors.initials: B
authors.lastname: Smyth
authors.forename: Jim
authors.initials: J
authors.lastname: McMenamin
authors.forename: Maria
authors.initials: M
authors.lastname: Zambon
authors.forename: Nick
authors.initials: N
authors.lastname: Phin
authors.forename: John M
authors.initials: JM
authors.lastname: Watson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000627:therapeutic use*; D002648:Child; D005191:Family Characteristics; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000188:drug therapy* / Q000453:epidemiology / Q000401:mortality / Q000635:transmission*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D058873:Pandemics / Q000517:prevention & control; D056990:Post-Exposure Prophylaxis; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000998:Antiviral Agents