In September 2012, USAID ENVISION partners worked closely with district and provincial health offices to test over 7,000 first and second year primary school students across 167 schools for presence of LF for USAID-funded transmission assessment surveys (TAS) for lymphatic filariasis (LF) in five districts in Sumatra Barat province.
Mass drug administration for elimination of LF has been taking place in these districts for at least five years. The TAS is the next step in determining whether those efforts have reached a threshold level of success where MDA can be discontinued and the disease will remain contained.
TAS is WHO global standard methodology and a critical component of an effective monitoring and evaluation program for elimination of LF.
WHO outlines three primary objectives for TAS:
- to provide a simple, robust survey design for documenting that the prevalence of lymphatic filariasis among 6–7 year old children is below a predetermined threshold;
- to provide the evidence base for program managers that MDA can be stopped; and
- to assure national governments that national programs have achieved their elimination goals.
To be eligible for TAS, a district must have completed at least five rounds of MDA with coverage exceeding 65% of the total population in each round; and microfilariae found in less than 1% of samples during sentinel and spot checks after the fifth MDA round.
In Indonesia, the program is closely coordinated and highly collaborative. In each district, there are four teams implementing TAS simultaneously. Provincial health office staff, district health office staff, two health center staff, as well as a supervisor from the national LF program conducted TAS activities in September. All staff were fully trained on their roles and the schools were sensitized and educated on the TAS process before the TAS team arrived.
Using a finger puncture technique, a small amount of blood is drawn and deposited on a rapid test strip. Within 25 minutes, health staff can tell if the student is infected with LF. These results can be quickly compiled to tell if the prevalence of LF in the evaluation unit is above or below the WHO predetermined threshold for stopping MDA. Districts that do not pass the TAS continue with two further rounds of MDA.
ENVSION Indonesia has worked with the Indonesia MOH to support TAS in five districts in 2012, two in 2013 and there are plans to carry out TAS in additional districts before the end of 2013.
 Monitoring and epidemiological assessment of mass drug administration in the Global Programme to Eliminate Lymphatic Filariasis: a manual for national elimination programmes. Geneva, World Health Organization, 2011 (WHO/HTM/NTD/PCT/2011.4).