tetano
Editor, Senior Moderator
J Infect Dis. 2012 Apr 9. [Epub ahead of print]
Estimates of influenza vaccine effectiveness for 2007-2008 from Canada's sentinel surveillance system: Cross protection against major and minor variants.
Janjua NZ, Skowronski DM, De Serres G, Dickinson J, Crowcroft NS, Taylor M, Winter AL, Hottes TS, Fonseca K, Charest H, Drews SJ, Sabaiduc S, Bastien N, Li Y, Gardy JL, Petric M.
Source
British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada.
Abstract
ObjectiveTo estimate influenza vaccine effectiveness(VE) for the 2007-2008 season and assess the sentinel surveillance system in Canada for monitoring virus evolution and impact on VE.MethodsNasal/nasopharyngeal swabs and epidemiologic details were collected from patients presenting to a sentinel physician within 7 days of influenza-like illness onset. Cases tested positive for influenza A/B by RT-PCR; controls tested negative. Hemagglutination inhibition(HI) and gene sequencing explored virus relatedness to vaccine. VE was calculated as 1-odds ratio for influenza in vaccinated versus non-vaccinated participants with adjustment for confounders.ResultsOf 1425 participants, 21% were immunized. Influenza was detected in 689(48%), of which 663 were typed/subtyped: 189(29%)A/H1, 210(32%)A/H3 and 264(40%)B. Of A/H1N1 isolates, 6% showed minor HI antigenic mismatch to vaccine with greater variation based on genetic identity. All A/H3N2 isolates showed moderate antigenic mismatch, and 98% of influenza B isolates showed major lineage-level mismatch to vaccine. Adjusted VE for A/H1N1, A/H3N2 and B components was: 69%(95%CI:44-83%), 57%(95%CI:32-73%), and 55%(95%CI:32-70%) with overall VE of 60%(95%CI:45-71%).ConclusionsDetailed antigenic and genotypic analysis of influenza viruses was correlated with epidemiologic estimates of VE showing cross-protection. A routine sentinel surveillance system that combines detailed virus and VE monitoring annually, as modeled in Canada, may guide improved vaccine selection and protection.
PMID:
22492921
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22492921
Estimates of influenza vaccine effectiveness for 2007-2008 from Canada's sentinel surveillance system: Cross protection against major and minor variants.
Janjua NZ, Skowronski DM, De Serres G, Dickinson J, Crowcroft NS, Taylor M, Winter AL, Hottes TS, Fonseca K, Charest H, Drews SJ, Sabaiduc S, Bastien N, Li Y, Gardy JL, Petric M.
Source
British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada.
Abstract
ObjectiveTo estimate influenza vaccine effectiveness(VE) for the 2007-2008 season and assess the sentinel surveillance system in Canada for monitoring virus evolution and impact on VE.MethodsNasal/nasopharyngeal swabs and epidemiologic details were collected from patients presenting to a sentinel physician within 7 days of influenza-like illness onset. Cases tested positive for influenza A/B by RT-PCR; controls tested negative. Hemagglutination inhibition(HI) and gene sequencing explored virus relatedness to vaccine. VE was calculated as 1-odds ratio for influenza in vaccinated versus non-vaccinated participants with adjustment for confounders.ResultsOf 1425 participants, 21% were immunized. Influenza was detected in 689(48%), of which 663 were typed/subtyped: 189(29%)A/H1, 210(32%)A/H3 and 264(40%)B. Of A/H1N1 isolates, 6% showed minor HI antigenic mismatch to vaccine with greater variation based on genetic identity. All A/H3N2 isolates showed moderate antigenic mismatch, and 98% of influenza B isolates showed major lineage-level mismatch to vaccine. Adjusted VE for A/H1N1, A/H3N2 and B components was: 69%(95%CI:44-83%), 57%(95%CI:32-73%), and 55%(95%CI:32-70%) with overall VE of 60%(95%CI:45-71%).ConclusionsDetailed antigenic and genotypic analysis of influenza viruses was correlated with epidemiologic estimates of VE showing cross-protection. A routine sentinel surveillance system that combines detailed virus and VE monitoring annually, as modeled in Canada, may guide improved vaccine selection and protection.
PMID:
22492921
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22492921