We conducted a confirmatory mapping survey to verify previous survey results which suggested that lymphatic filariasis is endemic in some parts of Lagos State, Nigeria. Finger-prick blood samples were collected from 2787 children aged 7-16years in 6 LGAs across 153 targeted schools. Circulating filarial antigen (CFA) levels were measured using the Filaria Test Strip (FTS), and LGAs were classified as endemic if there were up to three positive cases (d=3). CFA positive children were detected in all the 6 endemic LGAs, surpassing the critical cut off; Surulere (d=5, 1.36%, 95% CI 0.5-3.2%), Mushin (d=9, 1.9%, 95% CI 0.9-3.7%, Kosofe (d=10, 1.6%, 95% CI 0.8-3.1%), Oshodi (d=8, 1.6%, 95% CI 0.8-3.3%), Eti-Osa (d=9, 2.60%, 95% CI 1.3-5.1%), and Ikorodu (d=14, 3.0%, 95% CI 1.7-5.0%).All CFA positive children were ivermectin-naïve, and bed-net ownership (14, 25.5%, p=0.39) and usage (7, 50.0%, p=0.85) was low. About 29% (0-44%) of CFA positive children are likely to have acquired infection locally, and 71% (55.6-100%) could have acquired infection locally or elsewhere. Our findings underscore the possibilities of local and imported infections and justify the need to reintroduce MDA, optimize delivery of ITN and extend confirmatory mapping to areas previously classified as non-endemic.
Akogun et al. (Fri,) studied this question.