Effect of <i>Haemophilus influenzae</i> Type B and 13-Valent Pneumococcal Conjugate Vaccines on Childhood Pneumonia Hospitalizations and Deaths in Botswana

Abstract

Background: Globally, pneumonia is the leading cause of death among children. Few data exist regarding the effect of Haemophilus influenzae type B (Hib) vaccine and 13-valent pneumococcal conjugate vaccine (PCV-13) on the burden of childhood pneumonia in African settings. Methods: We collected data on children 1 to 59 months of age from patient registers at three hospitals in Botswana. Hib vaccine and PCV-13 were introduced in Botswana in November 2010 and July 2012, respectively. To evaluate the effect of Hib vaccine and PCV-13 introduction, we compared pneumonia hospitalizations and deaths pre-vaccine (January 2009 to October 2010) to post-vaccine (January 2013 to December 2017) using seasonally-adjusted interrupted time-series analyses. Findings: We identified 6943 pneumonia hospitalizations and 201 pneumonia deaths during the study period. In the pre-vaccine period, pneumonia hospitalizations and deaths increased by 1·8% (rate: 1·018; 95% CI: 0·994, 1·042) and 3·9% (rate: 1·039; 95% CI: 0·988, 1·093) per month, respectively. Vaccine introduction was associated with a 48·3% (95% CI: 28·9%, 62·4%) decrease in the number of pneumonia hospitalizations and a 50·1% (95% CI: 0·8%, 74·9%) decrease in the number of pneumonia deaths between the end of the pre-vaccine period (October 2010) and the beginning of the post-vaccine period (January 2013). During the post-vaccine period, pneumonia hospitalizations and deaths declined by 0·5% (rate 0.995; 95% CI: 0·990, 0·999) and 2·0% (rate: 0·980; 95% CI: 0·967, 0·993) per month, respectively. Interpretation: Pneumonia hospitalizations and deaths among children declined sharply following introduction of Hib vaccine and PCV-13 in Botswana. This effect was sustained for more than five years after vaccine introduction, supporting the long-term effectiveness of these vaccines in preventing childhood pneumonia in sub-Saharan Africa. Funding Statement: Melissa Ketunuti Endowment, Children’s Hospital of Philadelphia, American Academy of Pediatrics. Declaration of Interests: The authors have no conflicts of interest to disclose. Ethics Approval Statement: This study was approved by the Health Research and Development Committee (Ministry of Health, Botswana), ethics committees at each hospital site, and institutional review boards at the University of Botswana, the Children’s Hospital of Philadelphia, the University of Pennsylvania, and Duke University.