Factors associated with coverage in community-directed treatment with ivermectin for onchocerciasis control in Oyo State, Nigeria

Community-directed distribution with ivermectin (CDTI) has been adopted by the African Programme for Onchocerciasis Control (APOC) as its main strategy for achieving sustained high coverage in endemic communities. This article describes the coverage results achieved when CDTI was introduced in four local government areas of Oyo State, Nigeria. Using a household survey after the second distribution, researchers documented that 68.6% of the community overall received the drug, and as did 85.0% of those who were eligible (not pregnant, not sick and at least 5 years of age). Six factors were associated with having received ivermectin. Four were personal characteristics: being male, being at least 35 years of age, belonging to the Fulani ethnic minority, having taken the drug at a previous distribution. Two village characteristics were smaller size, as measured by number of houses, and use of the central place mode of distribution as opposed to house-to-house. In-depth interviews with village leaders and volunteer community-directed distributors (CDDs) and focus group discussions among villagers provided qualitative data to help interpret the findings. Women in many villages felt excluded from decision making. The concerns of migrant farm workers living in Yoruba farm settlements were not well understood by health staff or the majority population. The main factor associated with receiving the ivermectin was having received it before, and qualitative comments about side-effects and beliefs about orthodox drugs indicated that issues of personal preferences, not addressed in a household coverage survey, need to be explored further. The findings can provide guidance in re-orienting health workers to the importance of fostering participation and cohesion among all segments of the community, especially the inclusion of women and minority groups.