Nodules and dermatitis as signs of onchocerciasis in some communities of Aniocha North Local Government Area, Delta State, Nigeria

Abstract

Onchocerciasis is a major public health concern in sub-Saharan Africa as it affects all age groups and it causes irreversible blindness and severe skin problems in infected individuals. Infection with the disease in Nigeria has been under control with the introduction of Mass Administration of Medicine (MAM) with ivermectin in most affected communities for over a decade. This cross-sectional study which was carried out between November 2008 and March 2009 evaluated the prevalence of the disease in four ivermectin naïve farming communities namely Idumuogo, Ogodor, Anioma and Ubulubu of Aniocha North Local Government Areas of Delta State, Nigeria. Clinical manifestations of the disease were evaluated on consented 450 participants with the aim of proffering programmatic advice for ivermectin intervention. Data were analysed using SPSS version 16 into simple percentiles, and test for significance. Results showed that 55% (246/450) were males and 45% (204/450) females. An overall onchocerciasis prevalence of 54.22% was recorded across all communities studied. Males were significantly more infected than females (x² = 176.4, df = 24, p<0.01) with males having 56.91% (140/246) more clinical manifestation then females 50.98% (104/204). Although clinical signs were found in all age groups, it occurred mostly in older groups. Various degrees of cli nical manifestation recorded were: leopard skin 106 (24%), onchocercal nodules 32 (7.1%), onchodermatitis 51 (11.3%), itching 50 (11.1%) and impaired vision 18 (4.0%) with Idumuogo and Ubulubu, having the highest infections rates of 114 (25.3%) and 76 (16.9%) respectively. The result of the study showed that the communities surveyed were hypoendermic for onchocerciasis with a nodular rate of 32 (7.1%). This information is important to the ongoing elimination efforts of onchocerciasis in Nigeria as the few participants found with nodules could portend as reservoir for transmission where the vectors of the disease thrive. Continuous monitoring of the study-areas is advised so as to measure progress in MAM activities in the State.

Keywords: Onchocerciasis; Aniocha North; Delta State