Market survey of loiasis: prevalence and adverse reactions to ivermectin using a rapid procedure for loiasis

1. To assess the levels of endemicity of loiasis in a total of 30 selected villages covering an area of 5.2 sq km in Owo, Akure North, Akure South, Ondo East, Ondo West and Ifedore local governments in Ondo State, Nigeria, using Rapid Assessment for loiasis technique. 2. To obtain information on adverse reactions which occurred during previous administrations of the drug ivermectin used for the treatment of loiasis and onchocerciasis in the study area.

Consent was obtained from the chairman of each local government village head and individuals were co-opted into the study. A total of 480 individuals were interviewed, 80 from each of the six local governments, during the regular scheduled community market days. Survey for Loa loa was carried out according to specifications in "Guidelines for rapid Assessment of Loa loa (TDR, 2002).

Among the 480 respondents, 80 (16.7%) reported having had a history of loiasis while 11 (2.3%) had recent occurrence of the disease. The local name given to the disease in all the villages studied is "aran oju". Respondents in Ondo East local government had an eyeworm history of 23 (28.8%) and occurrence of loiasis was 02 (2.5%), these were the highest figures recorded. Using the SPSS version 10 package for data analysis, demographic factors of age and gender were not significant determinants of prevalence (> 0.05). Ondo East and Ifedore local governments had significant levels of loiasis prevalence (p < 0.05). Adverse reactions from the retrospective ivermectin administration was 04 (0.83%). This was statistically insignificant (p > 0.05).

Market surveys in rural communities were considered to be cost effective and rapid in the determination of prevalence of any disease. Since less than 40% of the respondents in the study area reported having had a history of eyeworm, the entire area was classified as "low risk" as regards the administration of ivermectin.