[Epidemiology of cutaneous leishmaniasis in five villages of Dogon country, Mali]. / Épidémiologie clinique et parasitologique de la leishmaniose cutanée dans cinq villages du Pays Dogon, Mali.

The epidemiology of the cutaneous leishmaniasis (CL) with Leishmania major is poorly documented in Mali. Following reports of CL in the tourist areas of the Dogon country (Bandiagara Escarpment), a joint French and Malian bio-clinical team conducted a field study from 16 to 27 January, 2010. The population of 5 villages has been examined by a dermato-infectiologist and cases were selected by visual inspection of skin lesions. Smears and biopsies (from the lesions) and venous blood were obtained from suspected cases of CL. Diagnosis was performed by light microscopy, in vitro cultures, serology and molecular biology. Fifty patients with skin lesions have been examined. Twenty-one have been suspected as CL. At least one sample was obtained from 18 patients. The lesions were predominantly old, more or less scarring and secondary infected. A skin smear was performed for 15 patients, a skin biopsy for 14 patients: smears and cultures were all negative. The PCR (Leishmania spp.) made on 14 biopsies was positive for 12 patients (86%). The low amount of amplified DNA obtained did not allow the sequencing and identification of the species of Leishmania. Western blot (WB) serology was positive in 11 cases out of 12 (92%). This investigation showed the presence of cutaneous leishmaniasis in Bandiagara. A further investigation is required during transmission period (September-October) to confirm the presence of Leishmania major epidemic in Dogon country.

In silico characterisation of putative Plasmodium falciparum vaccine candidates in African malaria populations.

Genetic diversity of surface exposed and stage specific Plasmodium falciparum immunogenic proteins pose a major roadblock to developing an effective malaria vaccine with broad and long-lasting immunity. We conducted a prospective genetic analysis of candidate antigens (msp1, ama1, rh5, eba175, glurp, celtos, csp, lsa3, Pfsea, trap, conserved chrom3, hyp9, hyp10, phistb, surfin8.2, and surfin14.1) for malaria vaccine development on 2375 P. falciparum sequences from 16 African countries. We described signatures of balancing selection inferred from positive values of Tajima's D for all antigens across all populations except for glurp. This could be as a result of immune selection on these antigens as positive Tajima's D values mapped to regions with putative immune epitopes. A less diverse phistb antigen was characterised with a transmembrane domain, glycophosphatidyl anchors between the N and C- terminals, and surface epitopes that could be targets of immune recognition. This study demonstrates the value of population genetic and immunoinformatic analysis for identifying and characterising new putative vaccine candidates towards improving strain transcending immunity, and vaccine efficacy across all endemic populations.

[Development of anti-malarial vaccines and need for clinical trials in accordance with international standards in South Africa]. / Le développement de vaccins antipaludiques et la nécessité des essais cliniques conformes aux normes internationales en Afrique.

In the 20th century malaria remains a major problem of public health in sub-Saharan Africa. This haemosporidium discovered in Africa by Laveran in 1880, kills one child every 30 seconds which amounts to three "tsunami" flowing each year into the African continent. The current international solidarity raises new hopes as regards the possibility to suppress the morbidity effects on the population's health condition. In order to be efficient, today's strategies (impregnated mosquito nets, intermittent preventive treatments, artemisinin based combination therapy) should reach at least 80% of the targeted population (pregnant women and children). By 2025, the uncontrolled urbanization of the African population and the social disorders will make a new population a target for malaria. The new data of functional genomics and proteonics open new avenues of research for new mechanisms, new therapeutics and vaccine targets and new tools of diagnosis and prognosis. The current candidate vaccines of the first generation have allowed the development of African competences in clinical trials of international standard. Although they represent scientific advances they will not resolve the problem of public health. Research on candidate vaccines of 2nd and 3rd generation remains a challenge for the international scientific community. Africa should play a determining role in this process. Scientific information on the field remains essential for these generations of new anti-malarial vaccines. The ethical aspects regarding those clinical trials and actions of public health and research remain an universal necessity Deontology and ethics are two complementary approaches for the good practice of medicine and research of a good practitioner. For the protection and advantages of the patient and/or volunteer of the research are the cornerstones of the ethical approach. The scientific quality of a research protocol submitted to an independent research ethics committee and the volunteer 's informed consent are universal ethical obligations. For the quality of ethics observance in a country reflects best the quality of the efficiency of its research system and its democracy.

[In vitro cultivation of fields isolates of Plasmodium falciparum in Mali]. / Culture in vitro d'isolats de terrain de Plasmodium falciparum au Mali.

Malaria immunology, molecular biology and pathogenicity studies often require the adaptation of Plasmodium falciparum field isolates to continuous in vitro cultivation. For this purpose we have established propagation protocols of asexual erythrocytic stages of P. falciparum samples from malaria patients or asymptomatic carriers in Mali. The parasites were grown in standard culture medium supplemented by human serum and in a culture medium without human serum but supplemented by AlbuMax 1. The candle jar environment and tissue culture flasks gassed with 5% CO2, 5% O2 and 90% N2 obtained from a portable gas mixer were used. Protocols for parasite cultivation in a resource-poor setting were developed. These protocols were successfully applied to fresh isolates in Mali as well as to blood samples frozen in liquid nitrogen and shipped to a laboratory in U.S.A.

[Seasonal variability of intestinal helminths and Schistosoma haematobium in a rural area of the Sahel in Mali]. / Variations saisonnières de l'infestation par les helminthes intestinaux et Schistosoma haematobium en zone rurale sahélienne au Mali

OBJECTIVE: The objective of this study was to determine the prevalence of intestinal helminths and Schistosoma haematobium before and after the rainy season in Pongonon, Mali. METHODS: Volunteers aged one year and above were included. The Kato-Katz method was used to detect eggs and cysts in stool samples, and Wattman filtration to detect S. haematobium eggs in urine samples. Two cross-sectional surveys were conducted in July and November 2007. RESULTS: In July (beginning of the rainy season), 304 volunteers were included; 278 were seen again in November (at the end of the rainy season). We found more intestinal helminths at the end of the rainy season (8.3%) compared to the beginning of the season (2.9%) (P = 0.01). There was no infection with S. haematobium in July but 7.6% in November (P < 0.001). The prevalence of intestinal helminths in children and adults was similar (P > 0.05), but the prevalence of infection with S. haematobium was higher in children aged 6 to 16 years (17/153) than in adults (2/74) (P = 0.02). CONCLUSION: Infections with helminth and S. Haematobium were both more prevalent at the end of the rainy season. Adults were infected as well as children and may constitute potential reservoirs of parasites. Effective control of these parasitic infections requires mass drug administration programs that take place during the seasons of high parasite egg excretion and that also include adult populations in some areas.