Lymphatic Filariasis in Benue State: Progress towards Elimination Based on Mass Drug Administration of Ivermectine and Albendazole

The Federal Government of Nigeria, through the Ministry of Health, commenced mass drug administration of ivermectine (IVM) and albendazole (ALB) in all the 36 States of the Federation in 2011. The objective of this research was to assess the progress towards the elimination of LF in some endemic Local Government Areas of Benue State. While MDA is continuing in six Local Government Areas, in the year 2024, we assessed the impact of MDA on LF prevalence in six Local Government Areas that had achieved five effective annual rounds of MDA. In 2023, a baseline mapping exercise was conducted in the 20 accessible LGAs in Benue State. The results revealed that fifteen out of the twenty LGAs were endemic for LF, with prevalence ranging from 1.0%-7.0%. The number of persons treated with ivermectine and albendazole in the fifteen LGAs was documented during annual MDA, and population-based cluster surveys were conducted at least once in each LGA during the five years of treatment, to verify the reported geographic and programme MDA coverage. This is the number treated divided by the total population eligible to receive treatment (usually <5years). The survey results confirmed that in six LGAs (Ukum, Logo, Konshisha, Katsina-Ala, Gboko, and Otukpa), the coverage exceeded the target of 65% while the other nine LGAs did not reach the recommended coverage. A pre-transmission assessment survey (pre-TAS) was conducted in one sentinel site and at least one spot check site in Ukum, Logo, Konshisha, Katsina-Ala, Gboko, and Otukpa in 2024 and was found to have LF antigenemia (LF Ag) < 2% (range 0.0% to 1.99%). In 2024, transmission assessment surveys (TAS) were conducted in the six LGAs that had previously passed the Pre-transmission assessment survey. The results showed that the six Evaluation units had achieved the LF Ag threshold required to stop MDA. Benue State had made significant progress towards LF elimination with six LGAs qualifying to stop treatment. However, nine other area councils still require a further two years of mass drug administration with effective MDA coverage before these LGAs qualify for impact assessment.