Prevalence of Human Onchocerciasis and Transmission Potential of Black Flies in Uba Community of Hong Local Government Adamawa State

Onchocerciasis remains a significant public health concern in rural Nigeria, particularly where black fly vectors are prevalent along rivers. This study assessed the potential black fly transmission and the prevalence of human onchocerciasis in the Uba community, Hong LGA, Adamawa State. From April to May 2023, 1209 Simulium flies collected from three settlements (A, B, C), spanning 9 km along River Yedzaram at Uba community were dissected and observed for microfilaria under the microscope. Additionally, 678 residents provided demographic data, underwent skin examination for onchocerciasis lesions, and had skin snips tested for microfilariae. Of the dissected flies, 14.64% (177/1209) harbored microfilariae, with higher rates in May compared to April, and heads were the primary infection site. Monthly transmission potential rose from 187.50 L3/person/month in April to310L3/person/month in May, signaling wet-season escalation. Overall prevalence in human is 11.06%, highest among males, those aged ≥35 years, and farmers. The study highlights ongoing transmission risk in Uba, under scoring the need for targeted ivermectin distribution and vector control during peak biting months to curb this neglected tropical disease.