Prevalence of malaria and its environmental and socio-cultural determinants in Tandahimba district council, Mtwara Region, Tanzania.

Background: Malaria remains a major public health and economic burden, especially in sub-Saharan Africa, which accounted for an estimated 94% of the 263 million global malaria cases and 597,000 deaths reported in 2023. In Tanzania, malaria prevalence is estimated at 8%, however regional disparities exist. Mtwara Region reported highest prevalence at 20% in 2022, increasing from 15% in 2017, despite the region's goal to eliminate malaria by 2030. Tandahimba district, in particular, has persistent high transmission despite ongoing control interventions, raising concerns about underlying environmental and socio-cultural factors to malaria transmission. This study aimed to determine the prevalence, environmental and socio-cultural influences linked with malaria cases in the Tandahimba District Council. Materials and Methods: A mixed-method study using a convergent parallel design was conducted. A multi-stage cluster sampling method was used to select 522 participants. Quantitative data were collected from these participants using structured questionnaires, while qualitative data were obtained through in-depth interviews with Ward Executive Officers and the District Vector Control Officer. Quantitative data were analysed using Stata version 17, applying a modified Poisson regression model to estimate adjusted prevalence ratios (aPRs) with 95% confidence intervals (CIs). Variables with p ≤ 0.05 were considered significant. Qualitative data were analysed thematically using NVivo and integrated with quantitative results to provide a comprehensive understanding. Results: Among the 522 participants, the mean age was 41 years (±22.5 SD). Maundo ward contributed the highest proportion of participants (24.1%). Environmental factors significantly associated with malaria included earth mud/grass wall materials (aPR = 1.47, 95%CI: 1.19-1.82, p < 0.001) and open eaves (aPR = 1.46, 95%CI: 1.23-1.73, p < 0.001), while metal sheet roofing was protective (aPR = 0.77, 95%CI: 0.69-0.86, p < 0.001). Socio-cultural factors such as travel history (aPR = 1.28, 95%CI: 1.07-1.53, p = 0.006) and staying outdoors at night (aPR = 1.29, 95%CI: 1.09-1.53, p = 0.003) increased malaria risk. Protective factors included bednet use, mosquito repellents, and mosquito sprays. Conclusions: Malaria prevalence in Tandahimba District is strongly influenced by environmental housing conditions and socio-cultural behaviours. Integrated, community-led interventions addressing housing improvements and preventive practices are essential for effective malaria control.