Low resistance of Plasmodium falciparum to mefloquine in Tanga region, Tanzania.

Studies were undertaken in the towns of Muheza, Korogwe and Tanga in Tanga region, north-eastern Tanzania in 1986 to assess the sensitivity of Plasmodium falciparum to mefloquine using an in vitro microtechnique. Successful tests were achieved on 29, 40 and 118 isolates from Korogwe, Muheza and Tanga respectively. The mean minimum inhibitory concentrations (logometric) were 0.52, 0.50 and 0.59 mumol per litre of blood for Korogwe, Muheza and Tanga respectively. Six isolates, 2 from Muheza and 4 from Tanga, showed resistance to mefloquine, having minimum inhibitory concentrations greater than 3.2 mumol per litre of blood. The chloroquine and mefloquine sensitivities of the isolates which showed mefloquine resistance were determined.