Background: Vaccines may reduce antibiotic use and the development of resistance.
Objectives: To provide a comprehensive, up-to-date assessment of the evidence base relating to the effect of vaccines on antibiotic use.
Data sources: Ovid MEDLINE, Embase, the Cochrane Library, ClinicalTrials.gov and WHO Trials Registry.
Study eligibility criteria: Randomized controlled trials (RCTs) and observational studies published from January 1998 to March 2018.
Participants: Any population.
Interventions: Vaccines versus placebo, no vaccine or another vaccine.
Methods: Titles, abstracts and full-texts were screened independently by two reviewers. Certainty of RCT evidence was assessed using GRADE.
Results: In all, 4980 records identified; 895 full-text reports assessed; 96 studies included (24 RCTs, 72 observational). There was high-certainty evidence that influenza vaccine reduces days of antibiotic use among healthy adults (one RCT; n = 4253; rate reduction 28·1%; 95% CI 16·0-38·4); moderate-certainty evidence that influenza vaccines probably reduce antibiotic use in children aged 6 months to 14 years (three RCTs; n = 610; ratio of means 0·62; 95% CI 0·54-0·70) and probably reduce community antibiotic use in children aged 3-15 years (one RCT; n = 10 985 person-seasons; risk ratio 0·69, 95% CI 0·58-0·83); and moderate-certainty evidence that pneumococcal vaccination probably reduces antibiotic use in children aged 6 weeks to 6 years (two RCTs; n = 47 945; rate ratio 0·93, 95% CI 0·87-0·99) and reduces illness episodes requiring antibiotics in children aged 12-35 months (one RCT; n = 264; rate ratio 0·85, 95% CI 0·75-0·97). Other RCT evidence was of low or very low certainty, and observational evidence was affected by confounding.
Conclusions: The evidence base is poor. Although some vaccines may reduce antibiotic use, collection of high-quality data in future vaccine trials is needed to improve the evidence base.
Prospero registration: CRD42018103881.
Keywords: Antibiotic; Global health; Meta analysis; Systematic review; Vaccine.
Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.