Environmental Exposure ; Humans

A study was carried out in south of Vietnam 15 Patients with Plasmodium falciparum gametocytes and asexual parasites were distributed into groups A, B and C. Artesunate was given orally at a total dose of 600 mg for 5 days in group A, 200 mg for 2 days in group B and intravenously at a total dose of 360 mg for 5 days in group C respectively. Gametocytes count was done before medication and daily after medication. Meanwhile, Anopheles dirus as a vector was employed to study the infectivity of gametocyte, The result showed that the mean gametocyte clearance time in three groups were respectively 15.4?5.0, 20.6?4.8 and 20.3?4.0 days. The mosquitoes were not infected from the blood in 2, 5 and 5 of 5 patients respectively on days 7, 14 and 21 in group A; 1 and 5 of 5 patients on day 14 and 21 in group B; 2 of 5 patients and 3 of 3 patients on days 14 and 21 in group C. It indicates that artesunate has remarkable effect on Plasmodium falciparum gametocytemia and its infectivity to mosquitoes.