Streptococcus pneumoniae is one of the greatest causes of diseases leading to child mortality, especially in low- and lower-middle-income countries. The aim of this review is to describe the prevalence of carriage of S. pneumoniae and the impact of vaccination among children aged under 5 years in low- and lower-middle-income countries since 2012.
The study was done as a systematic review of the literature. Relevant publications were searched in PubMed and screened systematically for information on prevalence of carriage of S. pneumoniae among children aged under 5 years. 149 publications were identified and 20 were included in the review.
The prevalence of S. pneumoniae ranged between 26.7% – 90.7%. The prevalence of vaccine-type carriage ranged between 4.4% – 57.6%, but generally decreased in countries after introduction of PCV, with a reduction of 15.6% – 65.7%. Half of the post- pneumococcal conjugate vaccine (PCV) studies reported a vaccine-type-carriage rate below 15%.
Vaccine-type-carriage has decreased in most countries with the introduction of PCV. Still, coverage is only moderate and carriage rates of S. pneumoniae vary greatly between countries. Continuous monitoring of carriage is needed to evaluate the effect of further introduction of PCV10 and PCV13.

Copyright © 2021. Published by Elsevier Ltd.