Effects of pertussis vaccination on transmission: vaccine efficacy for infectiousness.
We estimated the effect of pertussis vaccination on reducing transmission from vaccinated breakthrough cases from a comprehensive follow-up of a community of 30,000 residents in Niakhar, Senegal. Using a wide spectrum of case definitions, vaccine efficacy was estimated as 1 - the ratio of secondary attack rates (SAR) in all households with cases during the calendar year 1993, a pertussis epidemic year. Vaccine efficacy for infectiousness (VEi) was 85% (95% confidence interval (CI), 46-95%) for children vaccinated with three doses of a whole-cell (WC; 94%) or an acellullar (6%) pertussis vaccine, with pertussis defined as a cough >/=21 days with paroxysms confirmed by culture, serology, or contact with a culture-confirmed person. It was high for all case definitions. Partial vaccination reduced infectiousness. Pertussis vaccination is highly effective in reducing transmission from vaccinated breakthrough cases.
Préziosi
Marie-Pierre
MP
Niakhar Project, Institut de Recherche pour le Développement, Dakar, Senegal. mprezio@sph.emory.edu
Halloran
M Elizabeth
ME
D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007115:Immunization Schedule; D008297:Male; D018579:Patient Selection; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D012424:Rural Population; D012675:Senegal / Q000453:epidemiology; D014917:Whooping Cough / Q000453:epidemiology / Q000276:immunology* / Q000635:transmission
D010567:Pertussis Vaccine