Giuseppe
Emeritus
[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]
Eurosurveillance, Volume 18, Issue 5, 31 January 2013
Surveillance and outbreak reports
Vaccine effectiveness of 2011/12 trivalent seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: evidence of waning intra-seasonal protection
Surveillance and outbreak reports
Vaccine effectiveness of 2011/12 trivalent seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: evidence of waning intra-seasonal protection
R G Pebody (
)<SUP>1</SUP>, N Andr
ews<SUP>1</SUP>, J McMenamin<SUP>2</SUP>, H Durnall<SUP>3</SUP>, J Ellis<SUP>4</SUP>, C I Thompson<SUP>4</SUP>, C Robertson<SUP>5</SUP><SUP>,6</SUP>, S Cottrell<SUP>7</SUP>, B Smyth<SUP>8</SUP>, M Zambon<SUP>4</SUP>, C Moore<SUP>7</SUP>, D M Fleming<SUP>3</SUP>, J M Watson<SUP>1</SUP>
Citation style for this article: Pebody RG, Andrews N, McMenamin J, Durnall H, Ellis J, Thompson CI, Robertson C, Cottrell S, Smyth B, Zambon M, Moore C, Fleming DM, Watson JM. Vaccine effectiveness of 2011/12 trivalent seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: evidence of waning intra-seasonal protection . Euro Surveill. 2013;18(5)
ii=20389. Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20389
Date of submission: 24 July 2012 <HR>The 2011/12 season was characterised by unusually late influenza A (H3N2) activity in the United Kingdom (UK). We measured vaccine effectiveness (VE) of the 2011/12 trivalent seasonal influenza vaccine (TIV) in a test-negative case?control study in primary care. Overall VE against confirmed influenza A (H3N2) infection, adjusted for age, surveillance scheme and month, was 23% (95% confidence interval (CI): -10 to 47). Stratified analysis by time period gave an adjusted VE of 43% (95% CI: -34 to 75) for October 2011 to January 2012 and 17% (95% CI: -24 to 45) for February 2012 to April 2012. Stratified analysis by time since vaccination gave an adjusted VE of 53% (95% CI: 0 to 78) for those vaccinated less than three months, and 12% (95% CI: -31 to 41) for those vaccinated three months or more before onset of symptoms (test for trend: p=0.02). For confirmed influenza B infection, adjusted VE was 92% (95% CI: 38 to 99). A proportion (20.6%) of UK influenza A(H3N2) viruses circulating in 2011/12 showed reduced reactivity (fourfold difference in haemagglutination inhibition assays) to the A/Perth/16/2009 2011/12 vaccine component, with no significant change in proportion over the season. Overall TIV protection against influenza A(H3N2) infection was low, with significant intraseasonal waning.
- -------ews<SUP>1</SUP>, J McMenamin<SUP>2</SUP>, H Durnall<SUP>3</SUP>, J Ellis<SUP>4</SUP>, C I Thompson<SUP>4</SUP>, C Robertson<SUP>5</SUP><SUP>,6</SUP>, S Cottrell<SUP>7</SUP>, B Smyth<SUP>8</SUP>, M Zambon<SUP>4</SUP>, C Moore<SUP>7</SUP>, D M Fleming<SUP>3</SUP>, J M Watson<SUP>1</SUP>
- Health Protection Agency Health Protection Services ? Colindale, London, United Kingdom
- Health Protection Scotland, Glasgow, United Kingdom
- Royal College of General Practitioners Research and Surveillance Centre, Birmingham, United Kingdom
- Health Protection Agency Microbiology Services ? Colindale, London, United Kingdom
- University of Strathclyde, Glasgow, United Kingdom
- International Prevention Research Institute, Lyon, France
- Public Health Wales, Cardiff, United Kingdom
- Public Health Agency Northern Ireland, Belfast, United Kingdom
Citation style for this article: Pebody RG, Andrews N, McMenamin J, Durnall H, Ellis J, Thompson CI, Robertson C, Cottrell S, Smyth B, Zambon M, Moore C, Fleming DM, Watson JM. Vaccine effectiveness of 2011/12 trivalent seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: evidence of waning intra-seasonal protection . Euro Surveill. 2013;18(5)
ii=20389. Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20389 Date of submission: 24 July 2012 <HR>The 2011/12 season was characterised by unusually late influenza A (H3N2) activity in the United Kingdom (UK). We measured vaccine effectiveness (VE) of the 2011/12 trivalent seasonal influenza vaccine (TIV) in a test-negative case?control study in primary care. Overall VE against confirmed influenza A (H3N2) infection, adjusted for age, surveillance scheme and month, was 23% (95% confidence interval (CI): -10 to 47). Stratified analysis by time period gave an adjusted VE of 43% (95% CI: -34 to 75) for October 2011 to January 2012 and 17% (95% CI: -24 to 45) for February 2012 to April 2012. Stratified analysis by time since vaccination gave an adjusted VE of 53% (95% CI: 0 to 78) for those vaccinated less than three months, and 12% (95% CI: -31 to 41) for those vaccinated three months or more before onset of symptoms (test for trend: p=0.02). For confirmed influenza B infection, adjusted VE was 92% (95% CI: 38 to 99). A proportion (20.6%) of UK influenza A(H3N2) viruses circulating in 2011/12 showed reduced reactivity (fourfold difference in haemagglutination inhibition assays) to the A/Perth/16/2009 2011/12 vaccine component, with no significant change in proportion over the season. Overall TIV protection against influenza A(H3N2) infection was low, with significant intraseasonal waning.