Clinical Infectious Diseases (CID)
Volume 62 Issue 5 March 1, 2016
http://cid.oxfordjournals.org/content/current

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Advance Access
Protective Effect of Contemporary Pertussis Vaccines: A Systematic Review and Meta-analysis
T. Roice Fulton1,2, Varun K. Phadke3, Walter A. Orenstein4,6, Alan R. Hinman5, Wayne D. Johnson2, and Saad B. Omer1,2,4,6
Author Affiliations
1Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
2Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
3Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
4Emory Vaccine Center, Atlanta, Georgia, USA
5The Task Force for Global Health, Decatur, Georgia, USA
6Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
Abstract
Background.
Acellular (aP) and whole-cell (wP) pertussis vaccines are presumed to have similar short-term (<3 years after completion of the primary series) efficacy. However, vaccine effect varies between individual pertussis vaccine formulations, and many originally studied formulations are now unavailable. An updated analysis of the short-term protective effect of pertussis vaccines limited to formulations currently on the market in developed countries is needed.
Methods.
We conducted a systematic review and meta-analysis of published studies that evaluated pertussis vaccine efficacy or effectiveness within three years after completion (>3 doses) of a primary series of a currently available aP or wP formulation. The primary outcome was based on the World Health Organization (WHO) clinical case definitions for pertussis. Study quality was assessed using the approach developed by the Child Health Epidemiology Research Group (CHERG). We determined overall effect sizes using random effects meta-analyses, stratified by vaccine (aP or wP) and study (efficacy or effectiveness) type.
Results.
Meta-analysis of two aP vaccine efficacy studies (assessing the three-component GlaxoSmithKline and five-component Sanofi-Pasteur formulations) yielded an overall aP vaccine efficacy of 84% (95% confidence interval (CI), 81-87%). Meta-analysis of three wP vaccine effectiveness studies (assessing the Behringwerke, Pasteur/Merieux, and SmithKline Beecham formulations) yielded an overall wP vaccine effectiveness of 94% (95% CI, 88-97%) (both I2=0%).
Conclusions.
Although all contemporary aP and wP formulations protect against pertussis disease, in this meta-analysis the point estimate for short-term protective effect against WHO-defined pertussis in young children was lower for currently available aP vaccines than wP vaccines.