Reduced risk of pertussis among persons ever vaccinated with whole cell pertussis vaccine compared to recipients of acellular pertussis vaccines in a large US cohort

Clin Infect Dis. 2013 May;56(9):1248-54. doi: 10.1093/cid/cit046. Epub 2013 Mar 13.

Abstract

Background: Unexpected waning of immunity after pertussis vaccination is now well described. In this study we examined whether prior vaccination with whole-cell pertussis vaccine (wP) at any point provided superior protection contrasted with a solely acellular pertussis vaccine (aP) series. We utilized the coincidence of a large outbreak of pertussis with the termination of wP availability, providing populations of children who had been vaccinated with combinations of wP and aP.

Methods: Kaiser Permanente (KP) is an integrated healthcare system with complete electronic records and a centralized laboratory. Cases of laboratory-confirmed pertussis and vaccination data for members aged 8-20 years were retrieved.

Results: Among 263 496 persons aged 8-20 years, 904 cases of pertussis were identified. In patients with a full history of vaccinations administered by KP, those with 5 total doses of only aP had an 8.57 relative risk (RR) of pertussis (P < .0001) contrasted to those with ≥1 wP dose. With 6 doses of aP, the RR of disease was 3.55 (P < .0001). When external vaccine records were included, the results were similar.

Conclusions: We found a markedly increased risk of disease associated with an entirely aP series. This risk was mitigated, but not eliminated, by the presence of a sixth dose of pertussis vaccine (Tdap). Receipt of 1 or more wP doses markedly augmented the durability of immunity from subsequent aP doses. It appears that a wholly acellular pertussis vaccine series is significantly less effective and durable than one that contains the traditional whole cell vaccine.

MeSH terms

  • Adolescent
  • Child
  • Disease Outbreaks*
  • Female
  • Humans
  • Male
  • Managed Care Programs
  • Pertussis Vaccine / administration & dosage*
  • Pertussis Vaccine / immunology*
  • Prevalence
  • Risk Factors
  • United States / epidemiology
  • Vaccines, Acellular / administration & dosage
  • Vaccines, Acellular / immunology
  • Whooping Cough / epidemiology*
  • Whooping Cough / immunology
  • Whooping Cough / prevention & control*
  • Young Adult

Substances

  • Pertussis Vaccine
  • Vaccines, Acellular