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Background The current first-line treatments for uncomplicated malaria recommended by the National Malaria Control Programme in Mali are artemether–lumefantrine (AL) and artesunate–amodiaquine (ASAQ). From 2015 to 2016, an in vivo study was carried out to assess the clinical and parasitological responses to AL and ASAQ in Sélingué, Mali. Methods Children between 6 and 59 months of age with uncomplicated Plasmodium falciparum infection and 2000–200,000 asexual parasites/μL of blood were enrolled, randomly assigned to either AL or ASAQ, and followed up for 42 days. Uncorrected and PCR-corrected efficacy results at days 28 and 42. were calculated. Known markers of resistance in the Pfk13, Pfmdr1, and Pfcrt genes were assessed using Sanger sequencing. Results A total of 449 patients were enrolled: 225 in the AL group and 224 in the ASAQ group. Uncorrected efficacy at day 28 was 83.4% (95% CI 78.5–88.4%) in the AL arm and 93.1% (95% CI 89.7–96.5%) in the ASAQ arm. The per protocol PCR-corrected efficacy at day 28 was 91.0% (86.0–95.9%) in the AL arm and 97.1% (93.6–100%) in the ASAQ arm. ASAQ was significantly (p Pfk13 gene. Overall, for Pfmdr1, the N86 allele and the NFD haplotype were the most common. The NFD haplotype was significantly more prevalent in the post-treatment than in the pre-treatment isolates in the AL arm (p Pfcrt, the CVIET haplotype was the most common. Conclusions The findings indicate that both AL and ASAQ remain effective for the treatment of uncomplicated malaria in Sélingué, Mali.

Bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae represents a severe threat to rice cultivation in Mali. Characterizing the pathotypic diversity of bacterial populations is key to the management of pathogen-resistant varieties. Forty-one X. oryzae pv. oryzae isolates were collected between 2010 and 2013 in the major rice growing regions in Mali. All isolates were virulent on the susceptible rice variety Azucena; evaluation of the isolates on 12 near isogenic rice lines, each carrying a single resistance gene, identified six new races (A4 to A9) and confirmed race A3 that was previously reported in Mali. Races A5 and A6, isolated in Office du Niger and Sélingué, were the most prevalent races in Mali. Race A9 was the most virulent, circumventing all of the resistance genes tested. Xa3 controlled six of seven races (i.e., 89% of the isolates tested). The expansion of race A9 represents a major risk to rice cultivation and highlights the urgent need to identify a local source of resistance. We selected 14 isolates of X. oryzae pv. oryzae representative of the most prevalent races to evaluate 29 rice varieties grown by farmers in Mali. Six isolates showed a high level of resistance to X. oryzae pv. oryzae and were then screened with a larger collection of isolates. Based on the interactions among the six varieties and the X. oryzae pv. oryzae isolates, we characterized eight different pathotypes (P1 to P8). Two rice varieties, SK20-28 and Gigante, effectively controlled all of the isolates tested. The low association observed among races and pathotypes of X. oryzae pv. oryzae suggests that the resistance observed in the local rice varieties does not simply rely on single known Xa genes. X. oryzae pv. oryzae is pathogenically and geographically diverse. Both the races of X. oryzae pv. oryzae characterized in this study and the identification of sources of resistance in local rice varieties provide useful information to inform the design of effective breeding programs for resistance to bacterial leaf blight in Mali.

Malaria transmission largely depends on environmental, climatic, and hydrological conditions. In Mali, malaria epidemiological patterns are nested within three ecological zones. This study aimed at assessing the relationship between those conditions and the incidence of malaria in Dangassa and Koila, Mali. Malaria data was collected through passive case detection at community health facilities of each study site from June 2015 to January 2017. Climate and environmental data were obtained over the same time period from the Goddard Earth Sciences (Giovanni) platform and hydrological data from Mali hydraulic services. A generalized additive model was used to determine the lagged time between each principal component analysis derived component and the incidence of malaria cases, and also used to analyze the relationship between malaria and the lagged components in a multivariate approach. Malaria transmission patterns were bimodal at both sites, but peak and lull periods were longer lasting for Koila study site. Temperatures were associated with malaria incidence in both sites. In Dangassa, the wind speed (p = 0.005) and river heights (p = 0.010) contributed to increasing malaria incidence, in contrast to Koila, where it was humidity (p &lt, 0.001) and vegetation (p = 0.004). The relationships between environmental factors and malaria incidence differed between the two settings, implying different malaria dynamics and adjustments in the conception and plan of interventions.

Bacterial leaf blight caused by

OBJECTIVES In resource-limited settings, few data are available on virological failure after long-term first-line antiretroviral therapy. This study characterized the genotypic resistance patterns at the time of failure after at least 36 months of a first-line regimen in Mali, West Africa. METHODS Plasma samples from 84 patients who were receiving first-line antiretroviral treatment and with an HIV-1 RNA viral load (VL) >1000 copies/mL were analysed. Genotypic resistance testing was performed and HIV-1 drug resistance was interpreted according to the latest version of the National Agency for HIV and Hepatitis Research algorithm. RESULTS At the time of resistance testing, patients had been treated for a median of 60 months (IQR 36-132 months) and had a median CD4 cell count of 292 cells/mm(3) (IQR 6-1319 cells/mm(3)), a median HIV-1 RNA level of 28266 copies/mL (IQR 1000-2 93 495 copies/mL) and a median genotypic susceptibility score of 1 (IQR 1-4). The prevalence of nucleoside reverse transcriptase inhibitor (NRTI) and non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations was 78% and 82%, respectively. Viruses were resistant to at least one drug in 92% of cases. Although etravirine and rilpivirine were not used in the first-line regimens, viruses were resistant to etravirine in 34% of cases and to rilpivirine in 49% of cases. The treatment duration, median number of NRTI and NNRTI mutations and some reverse transcriptase mutations (T215Y/F/N, L210W, L74I, M41L and H221Y) were associated with the VL at virological failure. CONCLUSIONS This study demonstrated a high level of resistance to NRTIs and NNRTIs, compromising second-generation NNRTIs, for patients who stayed on long-term first-line regimens. It is crucial to expand the accessibility of virological testing in resource-limited settings to limit the expansion of resistance and preserve second-line treatment efficacy.

Evaluer l’épidémiologie du paludisme dans une cohorte randomisée d’enfants de 6 mois à 6 ans vivant dans deux villages à transmission palustre différente : Sotuba et Doneguébougou, Mali. Nous avons mené une étude de cohorte prospective avec un suivi longitudinal couplé de passages mensuels transversaux sur la chimioprophylaxie anti palustre. C’est une étude basée sur le choix d’un site potentiel pour le vaccin anti palustre de phase I. La randomisation a été faite sur le logiciel SPSS afin de repartir les sujets inclus en deux groupes par site. La chimio prophylaxie a été faite avec la chloroquine + Proguanil (CQ + PG). Le sex-ratio M/F était de 1,20 et 1,03 respectivement à Donéguébougou et Sotuba. L’indice plasmodique (IP) n’indiquait pas de variation significative (p= 0,50) entre les deux sites. L’indice splénique (IS) à l’inclusion montrait une variation significative entre les deux sites (p=0,0005). L’introduction de la chimio prophylaxie au cours des mois d’août et de septembre montre que la prémunition s’installait progressivement pendant les autres mois du suivi. L’incidence du paludisme étaitplus élevée à Donéguébougou (41,4 %) qu’à Sotuba (18.3 %). Ce qui était en rapport avec l’hyper endémicité palustre de Donéguébougou et la méso endémicité de Sotuba. Aucun enfant des 2 groupes à Sotuba n’avait été enregistré dans les accès 2. Dans le groupe contrôle deux enfants étaient allés au deuxième accès à Donéguébougou contre quatre à Sotuba. Les enfants sous chimio prophylaxie faisaient moins d’épisodes palustres que ceux du groupe contrôle. Le taux d’anthropophilie moyen d’An.gambiae Sl. à Donéguébougou (92.7%, n=2390) était comparable à celui observé à Sotuba (87,6%, n= 873) pour le même vecteur (p=0,000005).La chimioprophylaxie avait eu un effet significatif sur les indices paludométriques au niveau des deux sites. L’indice plasmodique était significativement différent, alors que le taux d’anthropophilie moyen restait comparable dans les deux sites. Donéguébougou pourrait être un bon site pour l’essai vaccinal de phase I. Les espèces An. gambiae sl, et An. funestus étaient les principaux vecteurs de la transmission.

Aware of the rapid spread of Ebola virus (EBOV) during the current West African epidemic, Mali took several proactive steps to rapidly identify cases within its borders. Under the Mali International Center for Excellence in Research program, a collaboration between the National Institute of Allergy and Infectious Diseases and the Malian Ministry of Higher Education and Scientific Research established a national EBOV diagnostic site at the University of Sciences, Techniques and Technologies of Bamako in the SEREFO Laboratory. Two separate introductions of EBOV occurred in Mali from neighboring Guinea, but both chains of transmission were quickly halted, and Mali was declared "Ebola free" on 18 January 2015 and has remained so since. The SEREFO Laboratory was instrumental in the success of Mali's Ebola response by providing timely and accurate diagnostics. As of today, the SEREFO Laboratory has tested 103 samples from 88 suspected cases, 10 of which were EBOV positive, since the Ebola diagnostics unit started in April 2014. The establishment of Ebola diagnostics in the SEREFO Laboratory, safety precautions, and diagnostics are described.

Diarrhea and malnutrition represent leading causes of death for children in Mali. Understanding a community's needs and ideas are critical to ensure the success of prevention and treatment interventions for diarrheal disease, as well as to improve food security to help reduce malnutrition. The objective of this study was to incorporate the Community Readiness Model (CRM) for the issues of childhood diarrheal disease and food security in Mali to measure baseline community readiness prior to any program implementation. Thirteen key respondents residing in Dioro, Mali were selected based on varied social roles and demographics and completed two questionnaires on these public health issues. The overall readiness score to reduce childhood diarrheal disease was 5.75 ± 1.0 standard deviation (preparation stage). The overall readiness score to improve food security was 5.5 ± 0.5 standard deviation (preparation stage). The preparation stage indicates that at least some of the community have basic knowledge regarding these issues, and want to act locally to reduce childhood diarrhea and improve food security and nutrition. Proposed activities to increase community readiness on these issues are provided and are broad enough to allow opportunities to implement community- and culturally-specific activities by the Dioro community.

Bacterial leaf streak (BLS) caused by Xanthomonas oryzae pv. oryzicola was first reported in Africa in the 1980s. Recently, a substantial reemergence of this disease was observed in West Africa. Samples were collected at various sites in five and three different rice-growing regions of Burkina Faso and Mali, respectively. Sixty-seven X. oryzae pv. oryzicola strains were isolated from cultivated and wild rice varieties and from weeds showing BLS symptoms. X. oryzae pv. oryzicola strains were evaluated for virulence on rice and showed high variation in lesion length on a susceptible cultivar. X. oryzae pv. oryzicola strains were further characterized by multilocus sequence analysis (MLSA) using six housekeeping genes. Inferred dendrograms clearly indicated different groups among X. oryzae pv. oryzicola strains. Restriction fragment length polymorphism analysis using the transcriptional activator like effector avrXa7 as probe resulted in the identification of 18 haplotypes. Polymerase chain reaction-based analyses of two conserved type III effector (T3E) genes (xopAJ and xopW) differentiated the strains into distinct groups, with xopAJ not detected in most African X. oryzae pv. oryzicola strains. XopAJ functionality was confirmed by leaf infiltration on ‘Kitaake’ rice Rxo1 lines. Sequence analysis of xopW revealed four groups among X. oryzae pv. oryzicola strains. Distribution of 43 T3E genes shows variation in a subset of X. oryzae pv. oryzicola strains. Together, our results show that African X. oryzae pv. oryzicola strains are diverse and rapidly evolving, with a group endemic to Africa and another one that may have evolved from an Asian strain.

The dynamics of reinfection by Schistosoma haematobium and Schistosoma mansoni after repeated treatment with praziquantel (40 mg/kg body weight, single dose) was studied in a cohort of schoolchildren living in an endemic area. A total of 214 urine and 220 stool samples were collected and examined at three different times, i.e., February 1989, July 1989 and February 1990. Mass chemotherapy was administered at the beginning of study (February 89). Treatment was repeated in children with positive tests at each subsequent sampling. Prevalence rates were 55.1 p. 100, 3.7 p. 100, and 35.0 p. 100 for Schistosoma haematobium and 62.7 p. 100, 46.3 p. 100 and 73.1 p. 100 for Schistosoma mansoni in February 1989, July 1989 and February 1990 respectively (p0.001). From July 1989 to February 1990, reinfection was observed in 84.5 p. 100 of children by Schistosoma haematobium versus 57.8 p. 100 by Schistosoma mansoni. The risk of reinfection by Schistosoma haematobium was higher in children between the ages of 7 and 10 years than in children between the ages of 11 and 15 years (p0.001), The incidence of intense Schistosoma haematobium egg excretion rose from 0 p. 100 in July 1989 to 6.0 p. 100 in February 1990. The incidence of intense Schistosoma mansoni excretion in February 1990 was 4.5 p. 100. The reinfection rate at 7 months was over 50 p. 100 for both parasite species despite repeated treatment. This finding demonstrates that additional measures such as proper sanitation and vector control are needed to control human schistosomiasis in irrigated rice paddies.

A study on the incidence and gravity of malaria among children suffering of sickle cell anemia was carried out in the pediatric hospital of Bamako-Mali. On the 236 cases of fever studied, 54.2% were malaria infected and 21.2% were carriers of the sicklemic trait. There was a significant difference between malaria affecting AA children and HbS children, specially concerning parasites load.

From May 1989 to June 1990 an experimental study has been undertaken in two village's malarial hyperendemy of the Malian savannah. This study's objective was to test the effectiveness, on paludometric parameters and the openness of the population to the impregnated curtains and blankets, of permethrin as strategy of controlling malaria. The experimental village (Tiénéguébougou) and the control one (Kambila) are located in the same ecosystem and as at least 3 km any from each other. The impregnated curtains were installed in all the experimental village's houses and all the 216 residents have received impregnated blankets. The entomological, parasitical and clinical parameters were measured monthly from may 1989 to november 1989. The impregnated curtains were accepted by the population. However the impregnated blankets were little successful. Their impact on the entomological parameters is remarkable with a reduction of more than 98% of ma and the rate of entomological inoculation (REI) in the houses. The reduction of parasitical index is much less perceptible. The effect on the parasitical pressure was manifested by a highly significant difference of splenic index between the two villages (lower in the control village). The main vectors belong to complex: A. gambiae s.l. which rate of parity was not affected by the impregnated material. Very efficient against the harmfulness of in house hematophagic insects, the curtains impregnated by pyrethroids are not sufficient for interrupting the transmission of malaria. Actually, the study is continued for 2 years with a best evaluation of the malarial morbidity.