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40Edward and Bernardfour villages being meso-endemic (60–89%) while theother eight were hypo-endemic (< 60%; Table 2).Communities with higher prevalence of LS andonchocercal nodule also have proportionately higherprevalence of skin microfilariae. Correlationcoefficient (r) = 0.64 was obtained when skin snipprevalence was compared with RAMs; there was,however, no correlation between microfilarialprevalence and visual impairment (r) = 0.017 in theEtulo area.10%. It is also important to train communities on howto conduct rapid assessment procedures in order toprioritize community eligibility.ACKNOWLEDGEMENTSWe acknowledge with thanks the assistance andsupport of National Onchocercosis ControlProgramme Coordinators for Buruku, Katsina-Alaand Okpokwu LGAs in carrying out the presentstudies.The prevalence of onchocercosis varied significantly REFERENCES(p < 0.05) in the different villages. Others have also Amuta EO and Olusi TA. 2000. Sero-epidemiological study ofreported varying endemicity within same Onchocerca volvulus using eluate of blood collected onbiogeographical zones (Nwoke et al., 1994; Nocks et filter paper. Nigerian Journal of Parasitology 21:33-38.al., 1998). It may be due to differences in duration and Carme B, Samba Y, Ntsoumou MV and Yebakima A. 1993.degree of exposure of members from different Prevalence of depigmentation of skin: a simple and cheapcommunities to bites of infected vectors (Nwoke et al., way to screen for severe endemic onchocercosis in Africa.1994) and immunological factors (Murdock, 1992). Bulletin of the World Health Organization 70: 755-758.Another reason might be topographical differences, Edungbola LD, Babata AL, Asaolu SO, Duke BOI and Connorwhereas Okpokwu area is characterized by hilly DH. 1990. Leopard skin and onchocercosis. Nigerianterrain with many fast flowing streams, the Etulo area Journal of Parasitology 9:77-82.is predominantly flat plain with few fast flowing Edungbola LD, Nwoke BEB, Onwurili COE, Akpa AUC andstreams. Tayo-Mafe M. 1993. Selection of rapid assessmentmethods for community diagnosis of onchocercosis.A total of 479 (89.4%) individuals who had Nigerian Journal of Parasitology 12:45-50.microfilariae in their skin biopsy showed no clinicalGemade EI and Dipeolu OO. 1983. Onchocerciasis in Benuesign of nodules or LS. Many other studies in NigeriaState of Nigeria. II. Prevalence of the disease among the Tivswhere skin snip, LS and palpable nodules were living in the Kwande local government area. Annals ofcombined to determine onchocercosis prevalence Tropical Medicine and Parasitology 77:513-516.revealed similar findings where LS and visibleGemade EI. 1993. Training manual in Rapid Assessmentnodules varied significantly (p < 0.05) with the Methods using nodules and Leopard skin, treatmentcommunity microfilarial rate (Nwoke et al., 1994; schedule based on weight and height and health educationNock et al., 1998). Amuta and Olusi (2000) also for large-scale distribution of Mectizan. Revised andreported high prevalence rate using skin snip in some updated by sight savers international (Nigeria). pp 42.villages where we recorded lower prevalence using LS Murdock ME. 1992. The skin and the immune response inand onchocercal nodules.onchocercosis. Tropical Doctor (Supplementary) 1:44-62.The very low incidence of blindness recorded in both Nock IH, Ripiye P and Galadima M. 1998. Diagnostic value ofstudy sites agreed with Nwoke et al. (1994) and has anodules and Leopard skin in community assessment ofhuman onchocercal endemicity. Nigerian Journal ofcommon observation because rainforest region ofParasitology 19:19-24.Nigeria is endemic for O. volvulus strains that rarelycause blindness unlike to savanna types which are Nwoke BEB, Edungbola LD, Mencias BS, Njoku AJ, AbanobOC, Nwogu, FU et al. 1994. Human onchocercosis in rainmore invasive and more pathogenic to the eyesforest zone of southern-eastern Nigeria. 1: Rapid(Nwoke et al., 1994).assessment methods for community diagnosis in Imo riverbasin. Nigerian Journal of Parasitology 15:7-18.The use of LS and palpable nodules as diagnosticprocedures for onchocercosis are highly desirable as Nwoke BEB, Dozie INS, Gemade EI and Jiya JY. 1998. Thethey are cheap, fast, convenient and highly efficient present status of human onchocercosis in southeasternNigeria using rapid epidemiological mapping (REMO).(Carme et al., 1993; Edungbola et al., 1993; Nwoke etNigerian Journal of Parasitology 19:11-18.al., 1998; Nock et al., 1998). A combination of thesetwo methods as done in this study is of exceptional Wentworth BB. 1988. Diagnostic Procedures for Mitotic andparasitic infections. American Public Health Associationadvantage since it identifies community's endemicity.Publication Inc. Washington DC. 637 pp.There is a need to commence treatment withivermectin in some of the villages investigated, WHO. 1995. Expert Committee Report on Onchocercosis.especially those with LS prevalence of more thanFourth Report, Technical Report Series. 253 pp. Geneva.