Emerging Infectious Diseases (Jun 2011)

Use of Antiviral Drugs to Reduce Household Transmission of Pandemic (H1N1) 2009, United Kingdom

  • Richard G. Pebody,
  • Ross Harris,
  • George Kafatos,
  • Mary Chamberland,
  • Colin Campbell,
  • Jonathan S. Nguyen-Van-Tam,
  • Estelle McLean,
  • Nick Andrews,
  • Peter J. White,
  • Edward Wynne-Evans,
  • Jon Green,
  • Joanna Ellis,
  • Tim Wreghitt,
  • Sam Bracebridge,
  • Chikwe Ihekweazu,
  • Isabel Oliver,
  • Gillian E. Smith,
  • Colin Hawkins,
  • Roland Salmon,
  • Brian Smyth,
  • Jim McMenamin,
  • Maria Zambon,
  • Nick F. Phin,
  • John M. Watson

DOI
https://doi.org/10.3201/eid1706.101161
Journal volume & issue
Vol. 17, no. 6
pp. 990 – 999

Abstract

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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 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%.

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