Effectiveness of four doses of pertussis vaccine during infancy diminished in elementary school age: A test-negative case-control study in Japan

Satoko Ohfuji, Kenji Okada, Yoko Mouri, Yuka Mihara, Shigeki Ishii, Akiko Miyata, Motoko Fujino, Chikako Motomura, Hiroaki Ito, Mitsuhiro Ohta, Yoshihito Kasahara, Hideo Nakamura, Masaki Hasui, Tetsushi Yoshikawa, Takaaki Tanaka, Takashi Nakano, Rie Koshida, Kaoru Araki, Megumi Hara, Yoshio Hirota

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5 Citations (Scopus)


Objective: The Japanese national immunization program recommends that children receive 4 doses of acellular pertussis vaccine between 3 months and 2 years of age. Nevertheless, the number of pertussis cases is increasing in elementary school children aged 6–12 years. Therefore, a test-negative case-control study was conducted to assess the effectiveness of the pertussis vaccine program. Methods: Subjects included children aged ≥3 months who visited a collaborating hospital due to pertussis-specific cough between October 2017 and November 2019. All subjects underwent diagnostic tests for pertussis, and those diagnosed as positive were regarded as cases. Subjects diagnosed as pertussis-negative were classified as controls. Vaccination history was collected using a questionnaire administered to parents with reference to immunization records. Logistic regression models were employed to calculate the odds ratio (OR) and 95% confidence interval for laboratory-confirmed pertussis. Results: Of 187 recruited subjects (120 cases and 67 controls), questionnaire responses were obtained for 145 subjects (95 cases and 50 controls). Compared with unvaccinated subjects, the vaccine effectiveness (VE) of 4 doses was 70% among all subjects and reached to 90% with marginal significance among subjects under 6 years of age. However, among school-aged subjects, the VE was not suggestive of protection against pertussis (VE: 8%). For vaccinees given 4 doses, the OR for developing pertussis increased significantly with longer duration since the fourth dose (compared with <4.5 years, OR of 6.0–8.2 years = 5.74; OR of ≥8.3 years = 3.88; P for trend by duration < 0.01). Conclusion: Effectiveness of administering 4 doses of pertussis vaccine during infancy decreases with time passed since the fourth dose. This regimen does not protect school-aged children against pertussis.

Original languageEnglish
Pages (from-to)11-17
Number of pages7
Issue number1
Publication statusPublished - 03-01-2021

All Science Journal Classification (ASJC) codes

  • Molecular Medicine
  • General Immunology and Microbiology
  • General Veterinary
  • Public Health, Environmental and Occupational Health
  • Infectious Diseases


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