COVID-19 vaccination coverage survey in population 18 years and older, Bissau, Guinea-Bissau, January 2023

Introduction: COVID-19 poses a serious problem to global public health. Despite vaccine availability, countries face difficulties in reaching the 70% coverage target. The objectives of this study were to estimate vaccination coverage for COVID-19 in the population aged 18 and older in Bissau, January 2023, and to assess factors associated with vaccination. Methods: A cross-sectional study was conducted using the WHO 30 by 7 cluster sampling technique. Based on this, a total of 210 interviews were estimated. Bissau’s selection was by convenience. The selection of clusters, blocks, households, and individuals to be interviewed was by simple random drawing. A vaccinated individual was defined as an eligible who provided proof, through a vaccination card or certificate, of at least one dose of the COVID-19 vaccine. Descriptive statistics, Prevalence Ratio (PR), 95% Confidence Intervals (95%CI), and Design Effect (DE) were calculated. Results: A total of 209 individuals were interviewed. The mean age was 37 (SD 0.89) years old; 59.3% (124/209) were female, 50% (104/209) were married, and 50.7% (106/209) were Christians. The vaccination coverage was 49% (102/209) with 95%CI: 42.0-56.0%, and DE=1.001. In bivariate analysis, married people (PR=1.5; [95%CI: 1.12-2.01]; DE=1.001) and having comorbidity (PR=1.37; [95%CI: 1.04-1.81]; DE=1.001) were more likely to be vaccinated. Conclusion: COVID-19 vaccination coverage in Bissau remained below the 70% target. Being married and getting vaccinated was an unusual finding that needs further study. The findings highlight the need for intensified vaccination campaigns and personalised strategies to improve coverage, particularly among unmarried individuals and those without comorbidities.