[Antimicrobial activity of Morinda morindoides on in vitro growth of vibrio cholerae in Côte d'Ivoire]. / Activité de Morinda morindoides sur la croissance in vitro du vibrion du choléra: expérimentation en Côte d'Ivoire.

Cholera is a major public health problem in developing countries. As a contribution to management of this disease, the study described herein was carried out in Côte d'Ivoire. The purpose was to evaluate the antibacterial activity of products obtained by various techniques from the leaves of Morinda morindoides on a pathogenic strain of Vibrio cholerae O:1. Morinda morindoides is a medicinal plant in the Ivorian pharmacopoeia. The products were obtained as aqueous extracts, 70% ethanolic extracts, residual extracts and a chromatographic fraction (BGG F5). All three extracts and the chromatographic fraction showed considerable in vitro antimicrobial efficacy against Vibrio cholerae O:1. The most active against in vitro growth of Vibrio cholorae O:1 was the 70% ethanolic extract with a minimal bactericidal concentration of 5 mg/ml. The antibacterial properties of this medicinal plant can be of great benefit for management of cholera.

Sulfadoxine-pyrimethamine susceptibilities and analysis of the dihydrofolate reductase and dihydropteroate synthase of Plasmodium falciparum isolates from Côte d'Ivoire.

Over a 2-year study period, three methods [a test of therapeutic efficacy, an in-vitro assay, and sequencing of the parasites' dihydrofolate-reductase (dhfr) and dihydropteroate-synthase (dhps) genes] were used to monitor sulfadoxine-pyrimethamine (SP) resistance in the Plasmodium falciparum strains infecting young children near Abidjan, the largest city in Côte d'Ivoire. Overall, 118 children aged<5 years and infected with P. falciparum were treated with SP. Twenty-one (23.5%) of the 89 children who completed the 14 days of follow-up were categorized as therapeutic failures. When P. falciparum isolates from the 61 children with adequate parasitaemias were investigated in the in-vitro assay, 24 (39.5%) were found to be highly resistant to pyrimethamine, each having a median inhibitory concentration (IC50) of at least 2000 nM. Polymorphism analysis of gene fragments of 118 P. falciparum isolates (one from each child enrolled in the study) revealed that 46 (39%) of the isolates had mutant dhfr and 111 (94%) had mutant dhps. The mutations mainly affected DHFR codon 108 (39% of the isolates) and DHPS codons 436 (65%), 437 (52%) and 613 (27%). Of the 37 DHFR mutant isolates from children who completed follow-up, 21 were from children with therapeutic failure, indicating that mutant DHFR was associated with resistance to pyrimethamine in vivo (kappa=0.61). A mutant dhfr genotype was also found to be strongly associated with resistance to pyrimethamine in vitro (kappa=0.79). There was, however, little evidence of an association between SP efficacy and dhps genotype (kappa=0.04). Resistance to SP appears to be an increasing problem in southern Côte d'Ivoire and one which may now justify a change away from this drug combination as the first- or second-line treatment for P. falciparum malaria in this area.

[In vivo evaluation of sulfadoxine-pyrimethamine efficacy during uncomplicated falciparum malaria in children of Yopougon (Abidjan, Côte d'Ivoire)]. / Evaluation in vivo de l'efficacité thérapeutique de l'association sulfadoxine-pyriméthamine au cours du paludisme non compliqué chez les enfants de Yopougon (Abidjan, Côte d'Ivoire).

The malaria, deadly parasite infection in its severe form, is widely spread in tropical zone where it rages in an endemic way. The emergence and the extension of Plasmodium resistance contributed to increase the morbidity and the mortality of this pathology in children under 5 years old. Facing the extend of this phenomenon, a monitoring of the expansion of the chemosensitivity proves to be necessary. The goal of the present study was to assess the sulfadoxine-pyrimethamine (S-P) efficacy according to the in vivo test WHO protocol of 14 days-follow-up. Children are treated to the S-P at the rate of 1/2 tablet per 10 kg of body weight in unique dose, then controls are done days 3, 7 and 14. At the end of this work, 179 on 475 subjects were effectively carriers of asexual parasites. So, the general plasmodic index and Plasmodium falciparum rate infection were respectively 37.7% and 100%. Among the 89 children followed until J14, those aged of 13 to 24 months represented 38% of the population of children suffering from Plasmodium malaria, against 7% of those aged between 49 and 59 months. In terms of therapeutic efficacy, 76.4% of adequate clinical and parasitological response (ACR) have been reached against 23.6% of therapeutic failure (TF).