Infectivity of Plasmodium falciparum gametocytes to Anopheles arabiensis after treatment with sulfadoxine-pyrimethamine.

Sulfadoxine-pyrimethamine induces increased gametocytaemia when used for treating Plasmodium falciparum malaria. Laboratory-reared Anopheles arabiensis mosquitoes were fed with blood from patients with post-therapeutic gametocytaemia using a membrane feeder. Fourteen days later the heads and thoraxes of 613 mosquitoes were negative for P. falciparum sporozoites by enzyme-linked immunosorbent assay.

Malaria outbreak control in an African village by community application of 'deet' mosquito repellent to ankles and feet.

The malaria vector Anopheles arabiensis Patton (Diptera: Culicidae) shows a marked predilection (> 80%) for biting the ankles and feet of human subjects, as revealed by our previous observations at Malahlapanga in the Kruger National Park, South Africa. Topical application of insect repellent, 15% deet (N,N-diethyl-3-methylbenzamide), to feet and ankles reduced the overall biting rate of An. arabiensis by 69%. A focal malaria epidemic in Albertsnek village (25 degrees 33'S, 31 degrees 59' E) near the Mozambique border, following flooding during February 2000, provided an opportunity to apply these findings of operational research for outbreak containment. Twice-nightly topical application of deet to ankles and feet of Albertsnek inhabitants was followed by rapid restoration of preepidemic malaria incidence levels after one incubation period. This encouraging outcome should be attempted in other outbreak-prone settings where infective mosquito bites are sporadic and malaria has unstable endemicity.

Do mosquito coils and killer sticks work against Anopheles gambiae sensu lato mosquitoes in Zimbabwe?

Tests against Anopheles gambiae s. 1. mosquitoes (malaria transmitting mosquitoes) were carried out in Chegutu, Chiredzi and Kamhororo (Gokwe). These tests were done in relatively closed rural huts and experimental huts. The tests demonstrated that a one hour exposure to smoke from the burning of insecticidal coils contain 0.3 pc pyrethrin, achieve 100 pc knockdown of mosquitoes. Mosquito killer sticks gave 85 pc knockdowns with 30 pc recoveries and less than 10 pc recoveries for the coils. With caged insects in Gokwe the KD50 for both the coils and sticks was been 15 to 20 minutes and the KD90 ranged from 40 to 50 minutes. The coils were observed to more lethal than the sticks. Mortalities were 100 pc for the coils and 85 pc for the killer sticks after a 24 hour holding period.

Knowledge attitudes and practices in relation to schistosomiasis in a rural community.

A knowledge attitudes and practices survey of sanitation, water supplies and schistosomiasis was carried out in a rural schistosomiasis endemic area of Zimbabwe. Questionnaires were administered to 349 households. No latrines were present in 61% of households and information on use, likes and dislikes was collected. Most drinking water was collected from sources presenting no risk of schistosomiasis whereas most washing activities were carried out at sites presenting such a risk. Schistosomiasis was thought to be a problem in the community by over 50% of households and 79% gave haematuria as a symptom of the disease. There was a correlation between the washing site and the reported presence of schistosomiasis in the family.