COVID-19 Vaccination in Adults: Results from the Tanzania HIV Impact Survey 2022-2023.

Background

During the COVID-19 pandemic, vaccine hesitancy was high in Tanzania. Reasons for vaccine hesitancy included skepticism about vaccine safety and efficacy. Nonetheless, by March 2023, following concerted efforts, Tanzania reported reaching a national COVID-19 vaccination coverage of 52.5% among adults. We analyzed COVID-19 vaccination status and perceived vaccine safety among adults aged ≥ 18 years using data from the Tanzania HIV Impact Survey (THIS) 2022-2023.

Methods

The THIS 2022-2023 was a nationally representative, cross-sectional household survey with a stratified two-stage cluster design. Descriptive analyses were conducted to determine the proportion of adults who self-reported receiving the COVID-19 vaccine andcompleting the primary vaccine series, and to assess vaccine safety perceptions. Analyses were weighted for non-response and accounted for complex survey design.

Results

Of 32,777 adults, 20.0% (95% confidence interval (CI): 18.9-21.1) reported receiving more than one COVID-19 vaccine dose. Of those, 82.9% (95% CI: 81.3-84.5) completed the primary vaccination series. The proportion of adults who reported vaccination increased with age from 12.5% among 18-24 year olds to 29.0% among those aged 55-64 years. Among adults living with HIV (ALHIV), 49.6% (95% CI: 47.1-52.1) were vaccinated, and vaccination rates increased with longer duration on antiretroviral therapy. Adults who perceived the vaccines as safe (27.9%, 95% CI: 26.4-29.3) were 10 times more likely to report being vaccinated than those who perceived the vaccines as "not at all safe" (2.7%, 95% CI: 2.0-3.6).

Conclusions

The COVID-19 vaccination coverage in Tanzania among adults ≥ 18 years as measured through the THIS 2022-2023 was less than half the national COVID-19 vaccine coverage reported in March 2023. ALHIV were more likely than the general population to be vaccinated. The substantial difference in vaccination rates between those who perceived the vaccines as safe versus unsafe highlights the importance of safety perception for vaccine uptake.