[Obstacles to laboratory diagnosis of malaria in Mali--perspectives]. / Problématique du diagnostic biologique du paludisme au Mali--perspectives.

Rapid accurate laboratory diagnosis is necessary for effective malaria management. In Mali, meeting this prerequisite is impeded by underuse of laboratory diagnosis by clinicians, absence of qualified laboratory facilities in some locations, and poor continuous professional education of laboratory technicians. The twofold aim of this investigation was to perform quality control of thick smear readings made by laboratory technicians in 1998 and 1999 and to study the feasibility and diagnostic value of two rapid diagnostic tests (RDT), i.e., ParaSight and OptiMAL, in comparison with the thick smear technique in the period from 1998 to 2003. Quality control of thick smear readings indicated a 56% false positive rate with 49.3% concordance between laboratory technician readings and the reference centre. Trials using RDT showed that the OptiMAL test was more efficient with 97.2% sensibility, 95.4% specificity and 93% concordance in comparison with thick smear. A program of training, refresher courses, and regular didactic supervision (quality control) for laboratory technicians has been set up in Mali under the sponsorship of the "Fondation Mérieux" (ACTION BIOMALI) and the President's Malaria Initiative (PMI). These institutions provide funding for training as well as equipment and consumables in all public medical laboratories in Mali. The thick smear method is still being used as the reference technique, but use of RDT is to be implemented at all levels of the health care pyramid.

[Randomized clinical trial of two malaria prophylaxis regimens for pregnant women in Faladie, Mali]. / Essai clinique randomisé de deux schémas de prévention contre le paludisme au cours de la grossesse à Faladiè (Mali).

From June 2003 to May 2004 we carried out a comparative study of two malaria prophylaxis regimens for pregnant women. The purpose was to compare the efficacy of two regimens using chloroquine (CQ) or sulfadoxine-pyrimethamine (SP) during pregnancy and delivery in a village located in an endemic area of Mali. The study was carried out in Faladié (District of Kati) located 80 km from Bamako. Prophylaxis was administered during the second and third trimesters of pregnancy (except the 9th month for SP). A total of 301 pregnant women were enrolled including 150 in the CQ group and 151 in the SP group. At the onset of the study, the two groups were comparable with regard to socio-demographic and malaria factors. At the time of delivery, malaria infection was reduced by 43.3% in the CQ group (P < 10-6), and by 79.1% in the SP group (p < 10-6). The anemia rate was reduced by 57.5% in the CQ group (Ch2 of McNemar = 0.017), and by 74.8% in the SP group (Ch2 of McNeamar = 0.025). The incidence of placental infection was 20.6 % in the CQ group versus 8.3 % in the SP group (p = 4.10-3). Overall 16.7% of newborns presented low birth weight at delivery including 70.4% in the CQ group. The findings of this study suggest that intermittent presumptive treatment using SP is more effective than intermittent presumptive treatment using CQ in protecting both the mother and newborn against intra-uterine malaria transmission and its consequences.

Entomological and parasitological parameters of malaria transmission in Douguia, Chad.

Malaria remains a threat for many countries, especially in Chad where it is the leading cause of morbidity and mortality. Few reliable data exist, however, about the entomological and parasitological parameters of malaria transmission. The objective of this study was to investigate the entomological and parasitological parameters of malaria transmission in Douguia, a village located 75 km northeast of Ndjamena (Chad), as part of a training program for participants in Chad's malaria control program. Mosquitoes were collected after morning pyrethroid spraying, with a mouth aspirator. The parasitological data were collected by a rapid diagnosis test or microscopic examination. The study examined 350 subjects aged from 6 months to 80 years. The plasmodic index (PI) of Plasmodium falciparum was 25.4 % (n = 89) and the gametocygenic index (GI) 9.1 % (n = 32); they varied significantly from one age group to another (p = 10- 3). The PI in pregnant women attending antenatal clinics was 18.7 % (n = 12/64). Three Anopheles species were found: Anopheles gambiae s.l, An. arabiensis and An. pharoensis. An. coluzzii accounted for 94.9 % of the An. gambiae s.s. The antigen sporozoite index (SI) was 4.5 %. Our results confirm the endemicity of malaria in Chad (Douguia) and underline the major role of An. gambiae s.l. in its transmission. However, repeated studies using PCR for Plasmodium detection would help to improve our understanding of its epidemiology.