MASS DIETHYLCARBAMAZINE CHEMOTHERAPY FOR CONTROL OF BANCROFTIAN FILARIASIS THROUGH COMMUNITY PARTICIPATION - COMPARATIVE EFFICACY OF A LOW MONTHLY DOSE AND MEDICATED SALT

The efficacy of 2 strategies for the control of bancroftian filariasis using diethylcarbamazine (DEC) mass chemotherapy delivered through co mmunity participation was evaluated and compared in 2 endemic communit ies in Tanzania with pre-treatment microfilarial (mf) prevalences of 3 4.7% and 31.0%, and mf geometric mean intensities (GMI) of 1122 mf/mL and 933 mf/mL, respectively. In the first community, all individuals a ged greater than or equal to 1 year were offered treatment for one yea r with a low monthly dose (50 mg DEC to children aged <15 years and 10 0 mg DEC to adults aged greater than or equal to 15 years; given indep endently of body weight), and in the second community all households w ere offered 0.33% w/w DEC-medicated cooking salt for one year. Both tr eatment strategies resulted in dramatic reductions in the mfloads. Amo ng those microfilaraemic before treatment, the low monthly dose and th e DEC-medicated salt gave mf clearance rates of 55.3% and 92.1%, respe ctively, and the pre-treatment mf GMIs were reduced by 99.4% and 99.9% , respectively, one year after starting treatment. At community level, the mf prevalences were reduced to 15.8% and 2.4% (reductions of 54.5 % and 92.3%) and the mf CMIs were reduced to 100 mf/mL and 32 mf/mL (r eductions of 91.1% and 96.6%), one year after starting treatment with the low monthly dose and DEC-medicated salt respectively. Males with h ydrocele before treatment improved remarkably one year after the start of treatment. Since both strategies were simple to administer and wel l accepted by the communities, they appear highly feasible for integra tion into large scale control programmes based on community participat ion.