Evaluation of influenza vaccine effectiveness and description of circulating strains in outpatient settings in South Africa, 2014

Authors

Johanna M. McAnerney, National Institute for Communicable DiseasesFollow
Florette Treurnicht, National Institute for Communicable Diseases
Sibongile Walaza, University of the Witwatersrand
Adam L. Cohen, U.S. Centers for Disease Control and Prevention
Stefano Tempia, U.S. Centers for Disease Control and Prevention
Senzo Mtshali, National Institute for Communicable Diseases
Lucille Blumberg, National Institute for Communicable Diseases
Cheryl Cohen, University of the Witwatersrand

Date of this Version

2015

Citation

McAnerney et al. (2015) Evaluation of influenza vaccine effectiveness and description of circulating strains in outpatient settings in South Africa, 2014. Influenza and Other Respiratory Viruses 9(4), 209–215.

Comments

Copyright 2015 The Authors. Used by permission.

Abstract

The effectiveness of the trivalent seasonal influenza vaccine during the 2014 season in South Africa was assessed using a test-negative case–control study design including 472 cases and 362 controls. Influenza A(H3N2) was the dominant strain circulating. The overall vaccine effectiveness estimate, adjusted for age and underlying conditions, was43.1% (95% CI: 26.8-74.5). 2014 H3N2 viruses from South Africa were mainly in sublineage 3C.3 with accumulation of amino acid changes that differentiate them from the vaccine strain in 3C.1.