Beyond Hesitancy: Assessing the vaccination gap among Children and Livestock in the Maasai community of Kajiado, Kenya

Despite established national immunization programmes for children and livestock, pastoral communities in Kenya remain chronically underserved, with low vaccination coverage attributed mainly due to seasonal mobility, vast terrain, and limited health infrastructure. Even less understood is whether these assumptions hold across all pastoral contexts, and how livelihood practices such as hiring herders during drought seasons may intersect with vaccine access. This study examined factors associated with child and livestock vaccination among Maasai communities in Kajiado Central Subcounty, Kenya, using a One Health lens. We employed a mixed-methods design across three wards (Dalalekutuk, Ildamat, and Purko). Quantitative data were collected through semi-structured household surveys (n=180), with bivariate analysis examining the associations between the vaccine hesitant group and the vaccine accepting group in children and livestock. Qualitative data were gathered through two gendered focus group discussions (FGDs, n=31) and seven key informant interviews (KIIs). Inductive thematic analysis was interpreted through the COM-B framework, and findings were integrated using convergent triangulation. Child immunization coverage averaged 90% (range 87-98%), which is higher than typically reported for pastoral populations. In contrast, livestock vaccination coverage averaged 53% (range 5-87%) despite comparable willingness to vaccinate in both children (97%) and livestock (93%). Vaccine hesitancy co-occurred across children and livestock within the same households (OR 36.7, 95% CI 5.9 - 227.5). Eighty-eight percent of households hired herders to migrate with livestock during the cool-dry season (June-September), suggesting a shift toward sedentarization. Qualitatively, supply chain failures including vaccine production monopoly, counterfeit vaccines, stockouts, and understaffing were identified as key contributors to low livestock vaccination coverage. Closing the livestock vaccination gap requires supply-chain reforms such as breaking the KEVEVAPI monopoly, strengthening the VMD regulatory framework, and securing transport budgets to avoid stockouts. The relationship between hiring herders and vaccine access warrants further investigation as a potential structural enabler towards strengthening pastoral health programming.