BackgroundMalaria remains a major public health problem, especially in tropical and subtropical regions because of the emergence and widespread of antimalarial drug resistance. Traditional medicine represents one potential source of new treatments. Here, we investigated the in vitro antiplasmodial activity of bark extracts from two Fabaceae species (Tetrapleura tertaptera and Copaifera religiosa) traditionally used to treat malaria symptoms in Haut-Ogooué province, Gabon.FindingsThe antiplasmodial activity of dichloromethane and methanolic extracts was tested on P. falciparum strains FCB (chloroquine-resistant) and 3D7 (chloroquine-sensitive) and on fresh clinical isolates, using the DELI method. Host cell toxicity was analyzed on MRC-5 human diploid embryonic lung cells using the MTT test.The dichloromethane extracts of the two plants had interesting activity (IC50 between 8.5 ± 4.7 and 13.4 ± 3.6 μg/ml). The methanolic extract of Tetrapleura tetraptera was less active (IC50 around 30 μg/ml) and the methanolic extract of Copaifera religiosa was inactive. The selectivity index (toxicity/antiplasmodial activity) of the dichloromethane extract of Tetrapleura tetraptera was high (around 7), while the dichloromethane extract of Copaifera religiosa had the lowest selectivity (0.6). The mean IC50 values for field isolates were less than 1.5 μg/ml for dichloromethane extracts of both plants, while methanolic extracts of Tetrapleura tetraptera showed interesting activity (IC50 = 13.1 μg/ml). The methanolic extract of Copaifera religiosa was also inactive on field isolates.ConclusionsDichloromethane extracts of Tetrapleura tetraptera and Copaifera religiosa, two plants used to treat malaria in Gabon, had interesting antiplasmodial activity in vitro. These data provide a scientific rationale for the traditional use of these plants against malaria symptoms. Bioactivity-guided phytochemical analyses are underway to identify the active compounds.

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Background and Purpose: Diarrhoeagenic E. coli (DEC) is one of the germs responsible for childhood diarrhea in developing countries. This study aims at determining the prevalence of the five main pathotypes of DEC isolated from faeces of children under five years old with diarrhea or not, living in the city of Koula-Moutou. Methodology: Isolates of E. coli were phenotypically screened on chromID TM agar and molecularly by multiplex PCR to detect the presence of enteroaggregative E. coli (EAEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enterohemorragic E. coli (EHEC) and enteroinvasive E. coli (EIEC). The evaluation of their sensitivity to 12 β-lactam antibiotic molecules was carried out by Kirby Bauer method. This method has also made it possible to characterize phenotypically the different β-lactamases produced. Results and Conclusion: Overall, at least one DEC pathovar was detected in the 63 E. coli strains with phenotypic and molecular frequencies of 63.5% and 68.5% respectively. Thus, ETEC (28.3%) and EHEC (28.3%) were the most frequent DEC in diarrheal isolates. ETEC/EHEC hybrid was recorded in both groups with rates of 7.5% in diarrheal cases and 10.0% for controls. The results showed produced carbapenemase type β-lactamases

Background Malaria remains a major public health issue in the world despite a decline in the disease burden. However, though symptomatic malaria is diagnosed and treated, asymptomatic infections remain poorly known and support transmission. This study assessed the prevalence of symptomatic and asymptomatic plasmodial infections in three areas in Gabon to monitor and evaluate the impact of malaria. Methods A cross-sectional study was conducted at the Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF). Febrile children and without fever, aged 6 months to 15 years from three localities (Franceville, Makokou, Lastoursville) in south-eastern Gabon were included in this study. The Plasmodium Spp infection was determined by microscopy and/or rapid diagnostic tests (RDT) followed by PCR according to the Snounou method. The data were recorded in Excel, and the statistical analyzes were performed using the software R version R 64x 3.5.0. Results Two thousand three hundred and eighty-one (2381) children were screened and included in this analysis. The mean age was significantly higher in asymptomatic children compared to symptomatic children. Hematological parameters varied significantly according to regions and clinical signs. The overall prevalence of Plasmodium infection was 40% (952/2381). In the urban area (Franceville) the prevalence of plasmodial infection was not significantly different between symptomatic and asymptomatic children. In contrast, a high prevalence of symptomatic plasmodial infection was found in infected children in rural and semi-rural areas. Among the three plasmodial species (Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale) identified, Plasmodium falciparum was the most widespread, and its prevalence was not significantly different between symptomatic and asymptomatic children in the three localities. In rural and semi-rural areas, a higher or lower prevalence of Plasmodium malariae was demonstrated in asymptomatic children. Conclusion This study showed that the prevalence of plasmodial infection varied according to the regions and clinical signs. The main species was Plasmodium falciparum, but in asymptomatic children the prevalence of Plasmodium malariae was high in rural areas. To help fight malaria more effectively asymptomatic infections should be taken into account and treated.