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Sanhitouo Charlemagne Dabiré,1,2 Marius K Somda,2 Léon W Nitièma,3 Dinanibè Kambiré,1 Samiratou Kiemtoré,1 Serge Théophile Soubeiga,1 Abdou Azaque Zouré,1 Konan Kouakou Toussaint Yao,2 Tegwindé Rebeca Compaoré,1 Henri Gautier Ouedraogo,1 Mamoudou H Dicko2 1Département Biomédical et Santé publique, Institut de Recherche en Sciences de la Santé ́(IRSS)/Centre National de la Recherche Scientifique et Technologique (CNRST), Ouagadougou, Burkina Faso; 2Département de Biochimie Microbiologie, Ecole Doctorale Sciences Et Technologies (EDST)/Université Joseph KI-ZERBO, Ouagadougou, Burkina Faso; 3Institut de l’Environnement et de Recherches Agricoles (INERA), Centre National de la Recherche Scientifique et Technologique (CNRST), Ouagadougou, Burkina FasoCorrespondence: Sanhitouo Charlemagne Dabiré, Email charlemagne_dabire@yahoo.frPurpose: The emergence of antibiotic resistance in pathogenic Enterobacteriaceae is a public health problem in tropical countries such as Burkina Faso. Antibiotic resistance could be identified using a variety of approaches. This study aimed to estimate the prevalence of pathogenic enterobacteria strains from three sources, as well as their antibiotic resistance profile to biotope and climatic season.Material and Methods: The methodological approach consisted of identifying Enterobacteriaceae from human (urine, stool), animal (eggs, milk, fish), and environmental (soil, lettuce) samples, followed by assessing their antibiotic susceptibility. Samples were collected from February to December 2023. Bacterial species were isolated and phenotypically identified (morphologically, culturally, biochemically, and antigenically) using standard methods. The prevalence of bacterial susceptibility to ten antibiotics was determined using the agar disk diffusion method. The collected data were analyzed with IBM SPSS Statistics 25 software.Results: A total of 615 Enterobacteriaceae isolates were collected, including 300, 168, and 147 samples from human, animal, and environmental sources respectively. Phenotypic characteristics allowed to partially identify 43 species, among these 29.76% belonged to Escherichia coli, 24.72% to Enterobacter cloacae, 13. 82% to Klebsiella pneumoniae, 3.41% to Enterobacter sakazakii and 2.6% to Klebsiella oxytoca. Bacterial resistance rates were: aminopenicillins (54.8%), first-generation cephalosporins (35.3%), sulfonamides (33.3%), third-generation cephalosporins (30.7%), fourth-generation cephalosporins (22.5%), fluoroquinolones (21.8%), phenicols (16.8%), and carbapenems (16.2%). The distribution of antibiotic resistance was 45.3% from human sources, 19.3% from animal sources, and 13.8% from environmental sources.Conclusion: The results indicate that resistant bacteria can come from any of the three biotopes, with human origin being the most frequent. The high prevalence of resistance to the antibiotics tested in isolated bacteria raises interest in investigating the genetic factors responsible.Keywords: pathogenic Enterobacteriaceae, biotopes, resistance, antibiotics, Burkina Faso

To obtain more information about rotavirus (ROTAV) genotypes in Burkina Faso, we characterized 100 ROTAVs isolated from fecal samples of children with acute gastroenteritis in the capital city of Ouagadougou, during December 2009-March 2010. Of note, 13% of the ROTAV-positive samples, including those with mixed infections, were positive for the unusual G6 genotype ROTAV strain. The genotypes identified were G9P[8], G6P[6], G1P[6], G3P[6], G1P[8], and G2P[4]. G9P[8] subgroup (SG)II strains dominated during the beginning of the ROTAV season, but later in the season, other G types associated with P[6] and SGI specificity emerged. This emergence was related to a shift in the overall age of infected children; ROTAV SGII infected younger children and induced more severe symptoms. The finding of a high incidence of G6P[6] strains highlights the need for long-term surveillance of ROTAV strains in Burkina Faso, especially when ROTAV vaccination is being considered in several African countries. [ABSTRACT FROM AUTHOR]

Translation initiation factors 4E (eIF4E) are the main source of resistance to potyvirus. We systematically assessed tomato single and double knock-out (KO) mutants of members of the eIF4E-coding gene family for resistance to Pepper veinal mottle virus (PVMV), a major constraint to tomato production. We show that the KO mutant of eIF4E2 has partial resistance to PVMV isolate IC, with plants harboring weak symptoms and low virus loads at the systemic level. The causal effect of eIF4E2 loss-of-function on resistance was confirmed on a progeny segregating for the KO mutation. The eIF4E2 KO mutant was resistant to six of the eight PVMV isolates tested and no resistance to other potyviruses was observed. This is the first evidence that mutation of eIF4E2 is in itself conferring resistance to a potyvirus and 3D protein modelling suggests that the eIF4E2 gene could be converted into a functional resistance allele., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The live oral rotavirus (RV) vaccines have shown a reduced efficacy in Africa. Recent in vitro studies have shown binding of the RV surface protein (VP4) to histo-blood group antigens (HBGAs) in an RV genotype-dependent manner, suggesting them to be putative receptors for RV. The diversity of HBGA phenotypes in different ethnic populations, combined with prevalence/absence of specific RV genotypes, led us to hypothesize whether the genetic variations in HBGAs in a population limit susceptibility to certain RV genotypes, plausibly leading to reduced vaccine efficacy., Methods: Association between HBGAs status and susceptibility to RV P genotypes was investigated in children in Burkina Faso and Nicaragua. In total, 242 children with diarrhea in Burkina Faso and Nicaragua were investigated, 93 of whom were RV positive., Results: In Burkina Faso, the P[8] RV strains (n = 27) infected only Lewis- and secretor-positive children (27/27; P < .0001), but no Lewis-negative children. In contrast, the P[6] strains (n = 27) infected predominantly Lewis-negative children (n = 18; P < .0001) but also Lewis-positive children, irrespective of their secretor status. The results from Nicaragua confirmed that all P[8]-infected children (n = 22) were secretor Lewis positive., Conclusions: As VP4 of genotype P[8] is a component of current RV vaccines, our finding that Lewis-negative children are resistant to P[8] strains provides a plausible explanation for the reduced vaccine efficacy in populations with a high percentage of Lewis-negative individuals, such as in Africa. Furthermore, our findings provide a plausible explanation as to why P[6] RV strains are more common in Africa., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: A significant fraction of cases of diarrhea, a leading cause of childhood mortality worldwide, remain unexplained., Objectives: To identify viruses in unexplained cases of diarrhea using an unbiased metagenomics approach., Study Design: Viral nucleic acids were enriched from the feces from 48 cases of unexplained diarrhea from Burkina Faso, sequenced, and compared against all known viral genomes., Results: The full genome of a highly divergent astrovirus was sequenced in a sample co-infected with parechovirus 1. RT-PCR identified a single astrovirus infection in these 48 patients indicating a low prevalence. Human astrovirus-BF34 was most closely related to mamastrovirus species 8 and 9 also found in human with which it shared 62%, 74%, and 57% amino acid identities over its protease, RNA dependent RNA polymerase and capsid proteins, respectively., Conclusions: Burkina Faso astrovirus is proposed as prototype for a novel species in the genus Mamastrovirus, here tentatively called Mamastrovirus 20, representing the fifth human astrovirus species., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Norovirus (NoV) constitutes the second most common viral pathogen causing pediatric diarrhea after rotavirus. In Africa, diarrhea is a major health problem in children, and yet few studies have been performed regarding NoV. The association of histo-blood group antigens (HBGA) and susceptibility to NoV infection is well established in Caucasian populations with non-secretors being resistant to many common NoV strains. No study regarding HBGA and NoV susceptibility has yet been performed in Africa. We collected 309 stool and 208 saliva samples from diarrheal children in Ouagadougou, Burkina Faso; May 2009 to March 2010. NoV was detected using real-time PCR, and genotyped by sequencing. Saliva samples were ABO, Lewis and secretor phenotyped using in house ELISA assays. NoV was detected in 12% (n = 37) of the samples. The genotype diversity was unusually large; overall the 37 positive samples belonged to 14 genotypes. Only children <2 years of age were NoV positive and the GII.4 NoVs were more frequent in the late dry season (Jan-May). NoV infections were observed less in children with the secretor-negative phenotype or blood group A (OR 0.18; p = 0.012 and OR 0.31; p = 0.054; respectively), with two non-secretors infected with genotypes GII.7 and GII.4 respectively. Lewis-negative (Le(a-b-)) children, representing 32% of the study population, were susceptible to GII, but were not infected with any NoV GI. GII.4 strains preferentially infected children with blood group B whereas secretor-positive children with blood group O were infected with the largest variety of genotypes. This is the first study identifying host genetic factors associated with susceptibility to NoV in an African population, and suggests that while the non-secretor phenotype provides protection; the Lewis b antigen is not necessary for GII infection.

Group A rotavirus (RVA) is the most common cause of severe gastroenteritis in young children globally, and responsible for a significant number of deaths in African countries. While vaccines are available, trials have shown a lesser efficacy in Africa. One of the reasons could be the prevalence and/or emergence of unusual or novel RVA strains, as many strains detected in African countries remain uncharacterized. In this study, we characterized RVA positive specimens from two remote rural areas in Burkina Faso, West Africa. In total 56 RVA positive specimens were subgrouped by their VP6 gene, and G-and P typed by PCR and/or sequencing of the VP7 and VP4 genes, respectively. Notably, we found a high prevalence of the unusual G6P[6]SGI strains (23%). It was the second most common constellation after G9P[8]SGII (32%); and followed by G1P[8]SGII (20%) and G2P[4]SGI (9%). We also detected a G8P[6]SGI strain, for the first time in Burkina Faso. The intra-genetic diversity was high for the VP4 gene with two subclusters within the P[8] genotype and three subclusters within the P[6] genotype which were each associated with a specific G-type, thereby suggesting a genetic linkage. The G6P[6]SGI and other SGI RVA strains infected younger children as compared to SGII strains (p<0.05). To conclude, in this study we observed the emergence of unusual RVA strains and high genetic diversity of RVA in remote rural areas of Burkina Faso. The results highlight the complexity of RVA epidemiology which may have implication for the introduction of rotavirus vaccines currently being evaluated in many African countries., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objective: There is limited information available regarding the etiology of gastrointestinal infections in Burkina Faso. The aim of this study was to investigate the prevalence and epidemiology of enteric pathogens causing gastroenteritis in young children, with a focus on rotavirus, and to investigate the levels of malnutrition and other clinical factors in association with the severity of diarrhea., Methods: A prospective study was undertaken from May 2009 to March 2010, covering the rainy and dry seasons, at the Saint Camille Medical Center in Ouagadougou, Burkina Faso. A total of 309 children less than 5 years of age with diarrhea were enrolled and examined for rotavirus, bacterial, and parasitic infections, as well as clinico-epidemiological aspects., Results: At least one enteropathogen was detected in 57.9% (n=179) of the children. Of these, 32.4% had rotavirus infections, 16.8% bacterial infections (enteropathogenic Escherichia coli 9.7%, Shigella spp 5.8%, and Salmonella spp 2.3%), and 18.8% parasitic infections (Giardia lamblia 11.3%, Trichomonas intestinalis 6.8%, Entamoeba histolytica/dispar 1.3%). During the cold dry period from December 2009 to February 2010, we observed a large increase in diarrhea cases, which was mainly attributed to rotavirus infections, as 63.8% of these diarrhea cases were positive for rotavirus. In contrast, no rotavirus infection was observed during the rainy season (June-September 2009), when the frequency of parasitic infections was high. Rotavirus and parasitic infections were age-related, with rotavirus being more prevalent in young children (<12 months) and parasites more common in older children (>12 months), while bacteria were equally prevalent among all age groups. Rotavirus infections exhibited more severe symptoms compared to bacteria and parasites, and were associated with fever, vomiting, and severe dehydration. Malnutrition, especially acute malnutrition (wasting), was significantly associated with more severe symptoms in rotavirus-induced diarrhea. The undernourished children also exhibited a prolonged duration of diarrheal episodes., Conclusion: This study demonstrates rotavirus as the main etiological agent in pediatric diarrhea in Burkina Faso, and further shows the great severity of rotavirus-induced diarrhea in undernourished children in Burkina Faso., (Copyright © 2011 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

An anaerobic digester fed with shea cake rich in tannins and phenolic compounds rich-shea cake and previously inoculated with anaerobic sludge from the pit of a slaughterhouse, enabled six months acclimatization of the bacteria to aromatic compounds. Afterwards, digester waste water samples were subject to successive culture on media with 1 g L(-1) tannic acid allowing the isolation of a bacterial strain coded AB. Strain AB was facultatively anaerobic, mesophilic, non-motile, non-sporulating, catalase and oxidase negative bacterium, namely strain AB, was isolated from an anaerobic digester fed with shea cake rich in tannins and phenolic compounds, after inoculation with anaerobic sludge from the pit of a slaughterhouse and enrichment on tannic acid. The coccoid cells occurred in pair, short or long chains and stained Gram-positive. Strain AB fermented a wide range of carbohydrates including glucose, fructose, galactose, raffinose, arabinose, sucrose, maltose, lactose, starch and cellulose. Optimum growth occurred with glucose and tannic acid at 37 degrees C and pH 8. The pH, temperature and salt concentration for growth ranged from 5 to 9, 20 to 45 degrees C and 0 to 15 g L(-1), respectively. Strain AB converted tannic acid to gallic acid. These features were similar to those of the Streptococcus genus. The determination of tannic acid hydrolysis end products, ability to utilize various organic acids, alcohols and peptides, GC% of the DNA, the sequencing of 16S rRNA gene and DNA-DNA hybridization will permit to confirm this affiliation and to determine the species.