Impact of pharmacy-based interventions on vaccination coverage among vulnerable and underserved populations: a...

Vaccination coverage remains suboptimal among vulnerable and underserved adult populations. We investigated the effectiveness of pharmacy-based interventions in improving vaccine uptake in high-risk groups and the most effective strategies.

A systematic search (PubMed/MEDLINE, Embase, Scopus; 26 July 2025) identified experimental and observational studies evaluating pharmacy-led vaccination interventions targeting adults ≥65 years or individuals aged 18-64 years with chronic conditions or limited healthcare access. The primary outcome was vaccination coverage. Odds ratios (ORs) were pooled using fixed- and random-effects models. Sensitivity analyses were conducted by intervention type and setting. Risk of bias was assessed using ROBINS-I, RoB 2, and NOS tools.

A total of 35 studies were included, encompassing over 1.3 million participants. In pre-post comparisons, pharmacy-based interventions nearly doubled vaccination uptake (random-effects OR = 1.88; 95% CI: 1.68-2.12). In case-control analyses, individuals exposed to pharmacist interventions were almost five times more likely to be vaccinated (random-effects OR = 4.87; 95% CI: 2.23-10.64). Multicomponent strategies and direct vaccine administration by pharmacists produced the most consistent improvements.

Pharmacist-led vaccination interventions significantly increase vaccine uptake among vulnerable adults. The most effective approaches involved pharmacists included eligibility assessment, counselling, administration, and documentation, integrated within routine care workflows.