Pertussis in children in an era of vaccination

Abstract

Background: Pertussis incidence has been increasing despite high early childhood vaccination coverage. Various strategies have been recommended to combat this problem which includes cocooning, booster doses for adolescents and young adults, and more recently maternal intrapartum vaccination. A previous report had highlighted an increase in pertussis in infants. This review was done to evaluate if there has been any change in the prevalence in the subsequent 10 years. Materials and Methods: Retrospective cohort study of admissions for pertussis in patients aged 0–18 years in a single-center tertiary maternal-pediatric hospital in Singapore from January 1, 2008, to October 31, 2017. Results: There were 221 cases identified. The majority were infants <6 months (89%) and of Malay (46%) ethnicity. About 54% were male and 81% were delivered term. Nearly, 69.7% had not received pertussis immunization. 64.2% had exposure to an unwell family member with respiratory symptoms. Cough was the most common presenting complaint (100%). High dependency or intensive care treatment was required in 21 cases (9.5%). Length of stay was significantly longer for infants under 6 months of age compared to those aged 6 months or older (additional 1.63 days, 95% confidence interval 0.57–2.68, P = 0.003). Coinfection was found in 23 cases, associated comorbidities in 22 cases, and both conditions in 3 children. There were 2 deaths and 11 readmissions. Conclusions: Pertussis in young infants in Singapore remains a significant healthcare burden despite current immunization strategies. Routine maternal vaccination to confer passive immunity on the newborn child may be beneficial to address this problem.