Hyperendemicity of Onchocerciasis in Ovia Northeast Local Government Area, Edo State, Nigeria|
Olusegun, Akinbo Frederick & Ehis, Okaka Christopher
Background: Onchocerciasis is a chronic parasitic infection caused by the filarial nematode, Onchocerca volvulus. The objective of this study was to determine the prevalence, endemicity, and symptomatic effects of the disease in Ovia Northeast Local Government Area.
Methods:The prevalence of Onchocerciasis was investigated in Ovia Northeast Local Government Area of Edo State, Nigeria, between March 2008 and June 2009 using the standard skin-snip method. A total of 2020 subjects, who had visited various primary health centres located in each community, were enlisted using randomised sampling, and the data were analysed using the Chi-squared (X2) test and logistic regression.
Results: Of the 2020 individuals examined, 1674 (83%) harboured microfilaria in their skin tissues. On the basis of the standardised scale for microfilaria prevalence—less than 10% is considered sporadic, 10–29% is considered hypoendemic, 30–59% is considered mesoendemic, and 60% and above is considered hyperendemic—the prevalence (83%) reported in this study led to the disease being classified as hyperendemic. Females were more frequently infected than were males, and this was statistically significant (P < 0.001). Prevalence was also found to increase with age, and this correlation was significant (P < 0.001). The prevalence of the clinical features of the disease in the local government area was 87.5% for leopard skin, 84.16% for itching, and 75.42% for nodules.
Conclusion: A prevalence of 83% was observed and considered hyperendemic. Female gender and age (50 years or more) were significant risk factors that affected the prevalence of Onchocerciasis. The findings demonstrated the hyperendemicity of infection and the need for urgent attention with ivermectin treatment and other control measures.
endemics, Nigeria, Onchocerca volvulus, Onchocerciasis, parasitology prevalence, risk factors