Evaluation of Southern Hemisphere influenza vaccine recommendations.
In 1999, the World Health Organization switched from annual to semi-annual recommendations for influenza vaccine composition. We compared the antigenic match between recommendations and circulating viruses before and after 1999, in the Northern and Southern Hemispheres. Vaccine match proportion for A/H3N2 viruses increased from 31% to 59% in the Southern Hemisphere (P<0.05), and is now comparable to that in the Northern Hemisphere. Vaccine match for influenza B decreased from approximately 100% to 33-54% in both hemispheres (P<0.05), following the unexpected resurgence of influenza B/Victoria in 1997. No estimate was available for influenza A/H1N1. We conclude that semi-annual vaccine recommendations are useful overall and discuss potential ways forward, including a recommendation for the improvement of vaccination policy and influenza surveillance in tropical areas.
Fogarty International Center, National Institutes of Health, 16 Center Drive,MSC 6705, Building 16, Bethesda, MD 20892, United States. richardst@mail.nih.gov
Stephanie A
SA
Richard
Cécile
C
Viboud
Mark A
MA
Miller
D006287:Health Planning Guidelines; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000276:immunology / Q000302:isolation & purification; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification / Q000276:immunology / Q000302:isolation & purification; D009981:Influenza B virus / Q000145:classification / Q000276:immunology / Q000302:isolation & purification; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control* / Q000821:virology
D007252:Influenza Vaccines