Abstract
INTRODUCTION: In Canada, pneumococcal vaccination is recommended to all adults aged ≥65 and those <65 who have one or more chronic medical conditions (CMCs). Understanding vaccine uptake and its determinants among eligible groups has important implications for reducing the burden of pneumococcal disease. METHODS: Using data from a large national cohort of Canadian residents aged ≥47 years between 2015-2018, we calculated self-reported pneumococcal vaccine uptake among eligible groups, estimated associations between key factors and non-vaccination, assessed missed opportunities for vaccination (MOV) and examined risk factors for MOV. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for relevant associations were estimated through logistic regression. RESULTS: 45.8% (95% CI: 45.2-46.5) of 22,246 participants aged ≥65 and 81.3% (95% CI: 80.5-82.0) of 10,815 individuals aged 47-64 with ≥1 CMC reported never having received a pneumococcal vaccine. Receipt of influenza vaccination in the previous year was associated with the lowest odds of pneumococcal non-vaccination (aOR = 0.14 [95% CI: 0.13-0.15] for older adults and aOR = 0.23 [95% CI: 0.20-0.26] for those aged 47-64 with ≥1 CMC). Pneumococcal vaccine uptake was also more likely in case of contact with a family doctor in the previous year (versus no contact), increased with age and varied widely across provinces. Among individuals recently vaccinated against influenza, 32.6% (95% CI: 31.9-33.4) of those aged ≥65 and 71.1% (95% CI: 69.9-72.3) of those aged 47-64 with ≥1 CMC missed an opportunity to get a pneumococcal vaccine. Among individuals who had contact with a family doctor, 44.8% (95% CI: 44.1-45.5) of those aged ≥65 and 80.4% (95% CI: 79.6-81.2) of those aged 47-64 with ≥1 CMC experienced a MOV. CONCLUSIONS: Pneumococcal vaccine uptake remains suboptimal among at-risk Canadian adults who are eligible for vaccination. Further research is needed to clarify the reasons behind missed opportunities for vaccination and adequately address the main barriers to pneumococcal vaccination.