Strategies Towards Meeting the Lymphatic Filariasis (LF) Elimination Goal in Tanzania

Lymphatic Filariasis (LF) is endemic across 119 districts in Tanzania. The Tanzanian Neglected Tropical Diseases Control Program (TZNTDCP) uses the drug package of Ivermectin+AIbendazole (IVM+ALB) during mass drug administration (MDA) as the primary strategy for achieving LF elimination. Surveillance and assessment of disease prevalence is also an important strategy to achieve elimination. Among the 119 LF-endemic districts, 105 have passed a transmission assessment survey (TAS) and have therefore stopped MDA. While the TZNTDCP continues surveillance in those districts which passed TAS, the focus is now on the remaining 14 districts with persistent LF transmission. After TAS2 and TAS3 were conducted in 2019, TZNTDCP added extra clusters that were positive in TAS1 and TAS2. No positive cases were reported in the extra clusters. Of the 14 districts still requiring MDA, 13 were scheduled for re-pre-TAS in 2020 after successfully reaching sufficient coverage in the last two rounds of MDA. During this re-pre-TAS, three to five sites within each district were selected. The sites included both sentinel and spot-check sites from previous assessments with a history of failure (Ag >2%) and new sites chosen from those with reported cases of LF and a history of low MDA coverage. Preliminary results showed that seven (7) of the 13 districts did not pass Pre-TAS, highlighting ongoing transmission. In response to these results, TZNTDCP will develop and implement new strategies to strengthen MDA and to reach all populations (including migrant populations) before the next disease-specific assessment (DSA). The strategies include allocation of community drug distributors (CDDs) according to the level of effort (applying the CDD ratio), implementing micro-plans at the sub-district level, and enhanced supportive supervision from the national level based on the need for each district. Moreover, DSA failure investigations will be conducted to critically analyze and provide recommendations related to why the districts did not pass the assessment. These strategies will help TZNTDCP move towards LF elimination in line with the World Health Organization's proposed target of eliminating LF as a public health problem by 2030.