COVID-19 vaccine confidence and its effect on vaccine uptake among people with hypertension or diabetes mellitus in Kilimanjaro region, Tanzania

Abstract

COVID-19 vaccination effectively reduces disease severity, hospitalization, and mortality, particularly among individuals with chronic conditions who bear a disproportionate burden of disease complications. Vaccine confidence–belief in its safety, effectiveness, and importance–boosts uptake. However, limited data on vaccine confidence in this population hinders the development of targeted interventions. This study examined COVID-19 vaccine confidence and its impact on uptake among individuals with hypertension or diabetes mellitus in the Kilimanjaro region, Tanzania. A community-based cross-sectional study was conducted in March 2023 among 646 randomly selected adults aged ≥18 years with hypertension or diabetes mellitus in three districts of Kilimanjaro region, northern Tanzania. An interviewer-administered electronic questionnaire assessed confidence and uptake of COVID-19 vaccines in addition to related knowledge and demographic characteristics. Data analysis was done for 646 individuals who consented to participate. Multivariable logistic regression models determined the factors associated with COVID-19 vaccine confidence and its effect on vaccine uptake. The proportion of COVID-19 vaccine confidence among all 646 participants was 70% and was highest for perceived vaccine importance (80%), followed by perceived vaccine effectiveness (77%) and perceived vaccine safety (74%). Good knowledge of COVID-19 vaccines and living in the Mwanga municipal council (MC), a semi-urban district, was independently associated with confidence in the vaccines’ importance, safety, effectiveness, and overall COVID-19 vaccine confidence. Confidence in COVID-19 vaccines increased the odds of vaccine uptake. Targeted interventions to boost vaccine confidence are therefore essential to enhance vaccine uptake in this high-risk population.