Circulating filarial antigens for monitoring the efficacy of ivermectin in treatment of filariasis

Seventy-three asymptomatic bancroftian filariasis patients with positive microfilaria in their blood films were included in this study. The patients were randomly divided into two groups: Ivermectin group given two doses [each of 100 ug/kg body weight three months apart] and 23 cases given two doses of placebo. The initial mean microfilaria [MF] count was 111/ml. At three months after ivermectin therapy, the mean MF became 7.8/ml and 24% of ivermectin treated cases had no detectable MF. At 6, 9 and 12 months; the mean MF count became 4.1, 6.5 and 11/ml with a microfilaria in 54%, 42% and 40% of treated cases, respectively. On the other hand, no statistically significant change in the mean MF count in placebo group was detected