Mass Drug Administration for Lymphatic Filariasis and Onchocerciasis for Liberia

Approximately 5,200 people will participate per year. The study population will include females and males over 5 years of age who live in filariasis and onchocerciasis endemic areas. Subject selection will not be based on health status. Two sites will be studied, and each study will last for 4 years. Participants will be studied only once in cross-sectional surveys. Some subjects may be included in more than one annual population survey, but this is not a longitudinal study. Investigators will compare annual and semiannual mass drug administration (MDA) for lymphatic filariasis and onchocerciasis, and investigators will compare the impact of these MDA schedules on soil transmitted helminth infections. MDA will be administered by others (Liberian Ministry of Health or Liberian Institute of Biomedical Research). The investigators will test the hypothesis that semiannual mass drug administration (MDA) is superior to annual MDA for elimination of lymphatic filariasis, onchocerciasis and for control of soil transmitted helminth (STH) infections. 1. Compare the relative impact and cost effectiveness of annual vs. twice yearly mass drug administration (MDA) for elimination of lymphatic filariasis (LF) in these populations. 2. Compare the relative impact and cost effectiveness of annual vs. twice yearly mass drug administration (MDA) for elimination of onchocerciasis in these populations. 3. Study the impact of annual vs. semiannual MDA on soil transmitted helminth (STH) infection in these populations. Continuation Activities (2019/2020): Additional one-time cross-sectional surveys will be completed in the Harper site in Maryland district in 2019 and in Lofa in 2020 to measure the long-term impact of MDA on W. bancrofti, O. volvulus, and on STH infection parameters following these cumulative 7-9 rounds of MDA since the baseline survey taken in 2013. Since the last DOLF surveys (3rd follow-ups) in these sites in 2016 \& 2017, respectively, there have been a total of 3