Factors that influence human exposure to fly bites in Fer Fer and Mustahil districts in Eastern Ethiopia-based on the experiences and views of members of the local communities

Riverine communities experience frequent contact with biting flies; however, questionnaire reports alone cannot identify the responsible insect taxon. We conducted a community-based cross-sectional questionnaire study among 409 adults from 12 settlements in the Fer Fer and Mustahil districts, eastern Ethiopia, to identify factors associated with self-reported fly bites near the Shabelle River during the preceding four weeks. Multivariable logistic regression with village-fixed effects was used. Overall, 57.21% reported a recent bite. Compared with residence > 3 km from the river, residence 1–3 km away (adjusted odds ratio [AOR] 4.33, 95% CI 1.97–9.51) and < 1 km away (AOR 29.09, 95% CI 12.58–67.24) were associated with higher odds of reported bites. Dense vegetation around the household was also associated with higher odds (AOR 4.14, 95% CI 2.25–7.61). River visit frequency showed a non-monotonic pattern, while age, gender, occupation, livestock proximity, time near the river, grazing area, knowledge, and attitude were not independently associated. These questionnaire-based findings identify river-adjacent and densely vegetated households as priorities for direct entomological investigation.