Vaccine Knowledge and Acceptance Among Hadzabe Hunter-Gatherers in Tanzania.

Objectives: Vaccines are highly successful in preventing disease, but misinformation has fueled vaccine hesitancy globally, thereby reducing immunization rates and weakening herd immunity. Vaccine knowledge and hesitancy among hunter-gatherers is a crucial area of research and intervention, as their mobile lifestyle exacerbates other challenges, such as marginalization and medical mistrust.

Methods: In our exploratory study, we surveyed 91 Hadzabe adults across six camps (mean age = 39, 46% female) about their knowledge of vaccines and their safety and efficacy. Differences between sexes and camps were tested using Fisher's exact tests.

Results: Half of participants reported not knowing what a vaccine is, while one-third described vaccines as protecting health or preventing disease. About 32% were unsure about vaccine safety, while most Hadzabe adults strongly agreed vaccines are effective (65.3%). A majority (72%) agreed vaccines are important for children, yet only one-third strongly agreed on their importance for adults. More females than males expressed uncertainty about the importance of adult vaccines (p = 0.03). Participants in our sample perceived vaccines as less effective and more safe than the general Tanzanian population, based on 2018 Wellcome data.

Discussion: In our sample, results indicate that while Hadzabe participants generally agree that vaccines are important, particularly for children, important gaps in vaccine knowledge remain. There is a clear need to communicate vaccine information to the Hadzabe community in a culturally appropriate manner. Such efforts are critical in safeguarding the health of Indigenous populations experiencing greater market integration, thereby supporting access to vaccines against diseases.