Impact of Mass Drug Administration (MDA) on the Transmission of Lymphatic Filariasis in Tono Irrigation Area in Navrongo, Ghana

摘要

Lymphatic filariasis is ranked as one of the leading causes of permanent and long-term disability and also oldest and most debilitating neglected tropical disease worldwide. Filariasis is caused by nematode endoparasitic worms transmitted to humans by various mosquito vectors. World Health Organization established Global Programme to Eliminate Lymphatic Filariasis as a public health problem by the year 2020. The strategies employed are to interrupt transmission through mass drug administration (MDA) and to alleviate suffering and disability via morbidity management; and vector control. It is expected that after implementation of the strategies above, transmission assessment surveys are required to ascertain their progress, impact and efficacies. As MDA was the main strategy, this work therefore determined impact of mass drug administration on the transmission of lymphatic filariasis in Tono Irrigation area in Navrongo following more than nine years of its implementation. Human landing and pyrethrum spray monthly collections of mosquitoes in Wuru and Saboro were dissected to determine the transmission level in the study area. The mosquitoes collected in the study comprised 90.22% (3,650) Anopheles species and 9.78% (386) Culex species with no Aedes or Mansonis species. The man biting rate computed from (Human Landing Catch) HLC was 162.25 bites/manight in Wuru and 143.75bites/manight in Saboro. Only 3An. species were infected with filarial parasites; 2 in Saboro with 2mf, and 1L2 in a mosquito in Wuru. However, there was no L3 stage recorded in any of the 3,560 mosquitoes macerated implying that there was no ongoing transmission of LF in the study sites since no infective bites were encountered. However, a follow up survey is required to assess the level of transmission since one survey is inadequate to declare the place free of LF. Keywords: Anopheles species, Wuchereria bancrofti, Mass Drug Administration, Lymphatic filariasis, Ghana