Population impact and effectiveness of sequential 13-valent pneumococcal conjugate and monovalent rotavirus vaccine introduction on infant mortality: prospective birth cohort studies from Malawi

King, C. et al. (2020) Population impact and effectiveness of sequential 13-valent pneumococcal conjugate and monovalent rotavirus vaccine introduction on infant mortality: prospective birth cohort studies from Malawi. BMJ Global Health, 5(9), e002669. (doi: 10.1136/bmjgh-2020-002669) (PMID:32912855) (PMCID:PMC7482521)

Abstract

Background: Pneumococcal conjugate vaccine (PCV) and rotavirus vaccine (RV) are key tools for reducing common causes of infant mortality. However, measurement of population-level mortality impact is lacking from sub-Saharan Africa. We evaluated mortality impact and vaccine effectiveness (VE) of PCV13 introduced in November 2011, with subsequent RV1 roll-out in October 2012, in Malawi. Methods: We conducted two independent community-based birth cohort studies. Study 1, in northern Malawi (40000population), evaluated population impact using change-point analysis and negative-binomial regression of non-traumatic 14–51-week infant mortality preintroduction (1 January 2004 to 31 September 2011) and postintroduction (1 October 2011 to 1 July 2019), and against three-dose coverage. Study 2, in central Malawi (465 000 population), was recruited from 24 November 2011 to 1 June 2015. In the absence of preintroduction data, individual three-dose versus zero-dose VE was estimated using individual-level Cox survival models. In both cohorts, infants were followed with household visits to ascertain vaccination, socioeconomic and survival status. Verbal autopsies were conducted for deaths. Results: Study 1 included 20 291 live births and 216 infant deaths. Mortality decreased by 28.6% (95% CI: 15.3 to 39.8) post-PCV13 introduction. A change point was identified in November 2012. Study 2 registered 50 731 live births, with 454 deaths. Infant mortality decreased from 17 to 10/1000 live births during the study period. Adjusted VE was 44.6% overall (95% CI: 23.0 to 59.1) and 48.3% (95% CI: −5.9 to 74.1) against combined acute respiratory infection, meningitis and sepsis-associated mortality. Conclusion: These data provide population-level evidence of infant mortality reduction following sequential PCV13 and RV1 introduction into an established immunisation programme in Malawi. These data support increasing coverage of vaccine programmes in high-burden settings.

• Item Type: Articles
• Additional Information: This work was funded by a Wellcome Trust Programme Grant (WT091909/B/10/Z) to NF, NC, RH; an investigator initiated grant by GlaxoSmithKline Biologicals to NC, NB-Z, NF; a Wellcome Trust Strategic Award to AC (Number: 085417ma/Z/08/Z); and MLW core grant strategic award to RH. RH and NF are supported by the National Institute for Health Research (NIHR) Global Health Research Unit on Mucosal Pathogens using UK aid from the UK Government
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Crampin, Professor Mia
• Authors: King, C., Bar-Zeev, N., Phiri, T., Beard, J., Mvula, H., Crampin, A., Heinsbroek, E., Hungerford, D., Lewckya, S., Verani, J., Whitney, C., Costello, A., Mwansambo, C., Cunliffe, N., Heyderman, R., and French, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Public Health
• Journal Name: BMJ Global Health
• Publisher: BMJ Publishing Group
• ISSN: 2059-7908
• ISSN (Online): 2059-7908
• Published Online: 09 September 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in BMJ Global Health 5(9): e002669
• Publisher Policy: Reproduced under a Creative Commons License