The long term effects of repeated diethylcarbamazine administration with special reference to microfilaraemia and elephantiasis.

The result of mass treatment with 50 mg diethylcarbamazine (DEC) per kg body weight followed by two annual selective retreatments in an area highly endemic for Brugia timori infections are described. The criteria for selective re-treatment are simple and practical for use in rural areas. An education programme was developed which focused on describing the relationship between adenolymphangitis and filarial infections, the danger of repeated attacks and the efficiency of DEC in eliminating these attacks. Motivated persons in the community were charged with the responsibility of promptly treating all cases with acute clinical manifestations. With this programme the microfilaria rate by finger prick decreased from 24% to 0%, and by Nuclepore filtration from 30% to 5%. The adenolymphangitis rate decreased from 46% to 11% and the "elephantiasis' rate from 17% to 4%.