prevalence and degree of resistance of Plasmodium falciparum to first-line antimalarial drugs: an in vitro study from a malaria endemic region in Yemen

Unpublished studies on antimalarial drug efficacy have found low levels of chloroquine resistance in Yemen. This study was carried out to determine the current prevalence of drug resistance in Plasmodium falciparum in Yemen to the main anti-malarial drugs and to determine the effective concentration[EC] values. The WHO standard protocol was used for the selection of subjects, collection of blood samples, culture techniques, examination of post-culture blood slides and interpretation of results. The in vitro micro-test Mark III was used for assessing susceptibility of P. falciparum isolates. The criteria for blood parasite density was met by 219 P. falciparum malaria patients. Chloroquine resistance was found in 47% of isolated P. falciparum schizonts. Mefloquine resistanfce was found in 5.2%. In addition, the EC50 and EC95 values in blood that inhibited schizont maturation in resistant isolates were higher than the normal therapeutic level of mefloquine. No resistance occurred against quinine or artemisinin, with no growth at hte cut-off level of quinine and inhibition of low concentrations of artemisinin. Our study confirmed the occurrence of chloroquine-resistant P. falciparum and a slow increase in the rate of this resistance; it is likely that resistance will increase further and spread over all the foci of malaria in Yemen. The low rate of mefloquine-resistant P. falciparum, was lower than that reported in Africa or Southeast Asia, but it is the first report of mefloquine resistance in Yemen. Finally, the isolates were sensitive to low-concentrations of quinine and artemisinin

Seroprevalence of rubella antibodies among a selected sample of women of childbearing age inSana'a, Yemen

This study was conducted to determine the prevalence and susceptibility rate of rubella virus infection among women of childbearing age in Sana'a, Yemen. a two stage sampling method was used to conduct a cases-sectional survey. Individuals were chosen randomly from selected sample units of adult females. A total of 482 women were included. the prevalence rate of rubella IgG antibody measured by ELISA technique was 94.6%. The overall susceptibility rate was 5.4% with a significantly increased susceptibility in younger age groups. despite the lack of a rubella vaccination program in Yemen, a high percentage of women are exposed to the wild virus through natural transmission by the time they reach adolescence. The seronegative female, however, may be at high risk of contracting the virus during pregnancy and exposing the fetus to the possibility of congenital rubella syndrome. It is recommended that rubella screening should be a part of the routine investigation in family planning centers