The effectiveness of maternal pertussis vaccination in protecting newborn infants in Brazil: A case-control study. Issue 36 (23rd August 2019)

• Record Type: Journal Article
• Authors: Fernandes, Eder Gatti; Sato, Ana Paula S.; Vaz-de-Lima, Lourdes R.A.; Rodrigues, Marcela; Leite, Daniela; de Brito, Cyro A.; Luna, Expedito J.A.; Carvalhanas, Telma Regina M.P.; Ramos, Maria Lígia Bacciote Nerger; Sato, Helena Keico; de Castilho, Euclides A.
• Is Part Of: Vaccine. Volume 37:Issue 36(2019)
• Page Start: 5481
• Page End: 5484
• Publication Date: 2019-08-23
• Subjects: Bordetella pertussis -- Maternal immunization -- Pertussis vaccine -- Case-control study -- Brazil; CI confidence interval -- DTaP diphtheria toxoid, tetanus toxoid, and acellular pertussis vaccine -- DTwP diphtheria toxoid, tetanus toxoid, and whole cells pertussis vaccine -- DTwP Hib-HBV – diphtheria tetanus-whole-cell pertussis + Haemophilus influenzae b + hepatitis B vaccine -- MoH Brazilian Ministry of Health -- OR odds ratio -- SINAN National Notifiable Diseases Information System database (Sistema de Informação de Agravos de Notificação) -- SINASC Information System on Live Births database (Sistema de Informação sobre Nascidos Vivos) -- Tdap tetanus toxoid, reduced diphtheria toxoid, acellular pertussis -- VE vaccine effectiveness; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2019.03.049
• Languages: English
• ISSNs: 0264-410X

Abstract

Abstract: Introduction: In 2014, the Brazilian Ministry of Health (MoH) recommended Tdap to pregnant women in response to a significant increase in the incidence of pertussis among infants. The present study assessed the effectiveness of maternal immunization in preventing pertussis in infants. Methods: An unmatched case-control study was undertaken in São Paulo State, Brazil from February 2015 to July 2016. Cases were infants aged <8 weeks at onset of pertussis reported to the Surveillance System and confirmed by real-time polymerase chain reaction or culture. Four to six healthy infants were selected as controls per case from birth certificates in the Information System on Live Births database. General characteristics and mother's vaccination status were compared between cases and controls. The vaccine effectiveness (VE) was calculated as 1 – odds ratio (OR). For the adjusted VE, the OR was calculated using logistic regression analysis. Results: Forty-two cases and 248 controls were enrolled in the study. Mothers of 8 cases (19.1%) and 143 controls (57.4%) were vaccinated during pregnancy, resulting in an unadjusted VE of 82.6% (95% confidence interval [CI], 60.8–92.3%). The VE was unchanged after adjusting for maternal age and monthly household income. Conclusion: Maternal pertussis vaccination during pregnancy was effective in protecting infants aged <8 weeks from pertussis.