Objective:To determine the evidence for non-specific effects of the Pneumococcal and Haemophilus influenza vaccine in children aged 5 years and under.
Data sources:A key word literature search of MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials, the European Union Clinical Trials Register and ClinicalTrials.gov up to June 2023.
Study eligibility criteria:Randomised controlled trials (RCTs), quasi-RCT or cohort studies.
Participants:Children aged 5 or under.
Study appraisal and synthesis methods:Studies were independently screened by two reviewers, with a third where disagreement arose. Risk of bias assessment was performed by one reviewer and confirmed by a second. Results were tabulated and a narrative description performed.
Results:Four articles were identified and included in this review. We found a reduction in hospitalisations from influenza A (44%), pulmonary tuberculosis (42%), metapneumovirus (45%), parainfluenza virus type 1–3 (44%), along with reductions in mortality associated with pneumococcal vaccine. No data on the Haemophilus vaccine was found.
Conclusions and implications:In this systematic review, we demonstrate that there is a reduction in particular viral infections in children aged 5 years and under who received the 9-valent pneumococcal conjugate vaccine which differ from those for which the vaccine was designed to protect against. While limited studies have demonstrated a reduction in infections other than those which the vaccine was designed to protect against, substantial clinical trials are required to solidify these findings.