Interventions to improve pneumococcal vaccination coverage: A systematic review and meta-analysis

Streptococcus pneumoniae is a widely spread human pathogen that can cause infections as severe as meningitis. The pneumococcal vaccination is the optimal approach to prevent morbidity and mortality, but the vaccination coverage is low despite several attempts to improve it. This meta-analysis assesses the impact of the interventions to increase vaccination coverage.

A meta-analytic review and a mixed-effects meta-regression on articles between 2013 and 2023 from PubMed, Web of Science and ScienceDirect that assessed the impact of interventions on pneumococcal vaccination coverage was performed. We included randomized controlled trials (RCTs) and comparative non-RCTs, and excluded reviews, non-comparative or retrospective studies, as well as the ones for which the full text was not available or did not present raw data on vaccination. A subgroup analysis was performed by study design, intervention type, facilitator and population characteristics.

16 articles were included out of 349 across three databases. Ten were RCTs and six were non-RCTs. Nine were from the USA, three from France and one from China, Zimbabwe, Singapore and Turkey respectively. Seven studies had physicians and four had pharmacists as facilitators. Most described direct interventions such as education and reminders. Ten focused on at-risk patients. The pooled relative risk (RR) was (1.06 [1.00, 1.13], p = 0.04), with an I ² of 17.05%. RCTs reported significantly lower effect sizes compared to non-RCTs (-0.69), p = 0.02. Indirect interventions showed lower effect sizes (-0.45, p = 0.06). Pharmacist-led interventions showed a positive, almost significant effect (0.43, p = 0.07).

This meta-analysis offers valuable insights into the factors that influence pneumococcal vaccination coverage and serves as a guide for the development of more effective and targeted strategies.