Persistence of onchocerciasis in villages in Enugu and Ogun states in Nigeria following many rounds of mass distribution of ivermectin

• Published in: BMC infectious diseases Vol. 22; no. 1; pp. 1 - 6
• Main Authors: Ekpo, Uwem F., Eneanya, Obiora A., Nwankwo, Edith N., Soneye, Islamiat Y., Weil, Gary J., Fischer, Peter U., Nwaorgu, Obioma C.
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 10.11.2022; BioMed Central; BMC
• Subjects: Clinical trials; Density; Drug therapy; Females; Gender; Health aspects; Infections; Ivermectin; Local government; Mass distribution; Mass drug administration; Nigeria; Nodules; Onchocerciasis; Patient outcomes; Risk factors; Skin; Statistics; Tropical diseases; Villages; Nigeria
• ISSN: 1471-2334; 1471-2334
• DOI: 10.1186/s12879-022-07811-7

Onchocerciasis is endemic in most local government areas (LGAs) in Enugu and Ogun states. Most meso- and hyper-endemic LGAs have received many rounds of ivermectin mass drug administration (MDA). This study aimed to determine the current prevalence of onchocerciasis in villages in Enugu and Ogun states that were formerly highly endemic and to assess progress toward elimination of the infection in areas believed to be at high risk for persistence. Cross-sectional community surveys were conducted 8 to 12 months after the last round of MDA in 16 villages (6 in Enugu state and 10 in Ogun state) in individuals aged [greater than or equal to] 18 years. Study participants were examined for the presence of palpable subcutaneous nodules. Skin snips from the posterior iliac crests were used to assess microfiladermia (Mf) prevalence and density. 643 subjects were palpated for nodules and 627 individuals (225 in Enugu state; 402 in Ogun state) provided skin snips. Nodule prevalence in the study villages ranged from 42 to 66.7% in Enugu state and from 0 to 25.0% in Ogun state. Mf prevalence in the Enugu and Ogun study villages ranged from 32 to 51.1% and 0 to 28.6%, respectively. Geometric mean skin Mf density in surveyed Enugu state villages ranged between 1 and 3.1 Mf/mg; these values were < 1 Mf/mg in all but one community in Ogun state villages.