Isolation and characterization of three novel Acinetobacter baumannii phages from Beninese hospital wastewater.

Acinetobacter baumannii is an opportunistic pathogen that is mostly associated with hospital-acquired infections. The rapid emergence of multi- and pan-drug-resistant Acinetobacter strains poses an increasing challenge in hospitals. Phage therapy offers one treatment option for infections caused by A. baumannii. We isolated three phages from Beninese hospital wastewater - fBenAci001, fBenAci002, and fBenAci003 - that infected clinical A. baumannii strains from Finnish patients. Phylogenetic analysis showed that these phages resemble phages of the genus Friunavirus, family Autographiviridae. The isolated phages meet the requirements set for phages used for phage therapy. However, they were found to have a narrow host range, which may limit their therapeutic use.

Investigating Catheter-Related Infections in Southern Benin Hospitals: Identification, Susceptibility, and Resistance Genes of Involved Bacterial Strains.

The use of catheters and bladder catheters in hospitals can increase the risk of bacterial infections. This study aimed to identify the bacterial strains involved in catheter-related infections (CRI) in southern Benin hospitals. The study included 407 samples, including 95 catheter tip samples and 312 urine samples collected from bladder catheters from patients on the first day and 48 h after admission. The catheter tip samples were analyzed using traditional bacterial isolation and identification methods, while the urine samples were analyzed using VITEK-2. Antibiotic sensitivity was tested using the Kirby Bauer method, and virulence and resistance genes were detected through standard PCR. The results showed a predominance of Escherichia coli (53.5%), Klebsiella pneumoniae (23.3%), and Enterobacter aerogenes (7.0%) among Gram-negative bacilli, and coagulase-negative Staphylococcus as the most identified cocci. Bacterial susceptibility to antibiotics showed variable levels of resistance, with blaTEM being detected in 42.9% of identified bacterial species, followed by blaSHV (26.2%) and blaCTX-M-15 (16.7%). The blaNDM gene was only found in three identified bacterial strains, while vanA and vanB genes were detected in 3.2% of strains with a prevalence of 55% for the mecA gene. A prevalence of 18.8% for fimH was noted for the virulence genes. In conclusion, this study highlights the importance of following proper hygiene and aseptic practices during catheterization to effectively prevent CRIs. These findings should be used to improve interventions in hospitals and reduce healthcare-associated infections in developing countries.

Prevalence and Antimicrobial Resistance of Campylobacter coli and Campylobacter jejuni Isolated from Pig Guts, Pig Feces, and Surface Swabs from the Cutting Tables at Slaughterhouse and Taverns in Southern Benin.

Campylobacter food-borne infections are a serious public health problem. In Benin, there is a proliferation of pork consumption in several forms. This study aims to determine the prevalence and the antimicrobial resistance of Campylobacter coli and Campylobacter jejuni strains isolated from pig guts, pig feces, and surface swabs from the cutting tables in southern Benin. For this purpose, 200 samples of pig guts, 40 samples of swabs from the cutting table surface, and 8 samples of pig feces were collected and subjected to bacteriological examination. The method used for the identification of bacteria was microbiological culture combined with molecular identification by PCR. The identified strains were then subjected to antibiotic susceptibility testing according to the methodology recommended by the EUCAST. Antibiotic profiles were compared between strains isolated from pig guts, pig feces, and cutting table surfaces on the one hand and among the different sampling sites on the other hand. The results obtained show that 47.6% of the samples analyzed were contaminated by Campylobacter spp. Molecular identification revealed 34.7% of Campylobacter coli and 9.3% of Campylobacter jejuni. The study of antimicrobial susceptibility showed resistance to ciprofloxacin, 44% to ampicillin, 23.9% to erythromycin, 11% to gentamicin, and 10.1% to amoxicillin + clavulanic acid. In total, 90.8% of the isolated Campylobacter strains were multidrug resistant. The use of antimicrobials in livestock production systems has increased considerably, which could explain, at least partially, the prevalence of Campylobacter and the resistance of strains to antibiotics. To limit the risk of Campylobacter food-borne infections, it is therefore important to include Campylobacter in the list of pathogens to be tested during sanitary quality control of meat and meat products in Benin.

Whole genome analysis of rotavirus strains circulating in Benin before vaccine introduction, 2016-2018.

Species A rotaviruses (RVA) still play a major role in causing acute diarrhea in children under five years old worldwide. Currently, an 11-gene classification system is used to designate the full genotypic constellations of circulating strains. Viral proteins and non-structural proteins in the order VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5/6 are represented by the genotypes Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx, respectively. In Benin, ROTAVAC® vaccine was introduced into the Expanded Programme on Immunization in December 2019. To monitor circulating RVA strains for changes that may affect vaccine performance, in-depth analysis of strains prior to vaccine introduction are needed. Here we report, the whole-gene characterization (11 ORFs) for 72 randomly selected RVA strains of common and unusual genotypes collected in Benin from the 2016 to 2018 seasons. The sequenced strains were 15 G1P[8], 20 G2P[4], 5 G9P[8], 14 G12P[8], 9 G3P[6], 2 G1P[6], 3 G2P[6], 2 G9P[4], 1 G12P[6], and 1 G1G9P[8]/P[4]. The study strains exhibited two genetic constellations designed as Wa-like G1/G9/G12-P[6]/P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 and DS-1-like G2/G3/G12-P[4]/P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Genotype G9P[4] strains possessed a DS-1-like genetic constellation with an E6 NSP4 gene, G9-P[4]-I2-R2-C2-M2-A2-N2-T2-E6-H2. The mixed genotype showed both Wa-like and DS-1-like profiles with a T6 NSP3 gene G1/G9P[8]/[4]-I1/I2-R1/R2-C1/C2-M1/M2-A1/A2-N1/N2-T1/T6-E1/E6-H1/H2. At the allelic level, the analysis of the Benin strains, reference strains (with known alleles), vaccine strains (with known alleles) identified 2-13 and 1-17 alleles for DS-1-like and Wa-like strains, respectively. Most of the study strains clustered into previously defined alleles, but we defined 3 new alleles for the VP7 (G3 = 1 new allele and G12 = 2 new alleles) and VP4 (P[4] = 1 new allele and P[6] = 2 new alleles) genes which formed the basis of the VP7 and VP4 gene clusters, respectively. For the remaining 9 genes, 0-6 new alleles were identified for both Wa-like and DS-1-like strains. This analysis of whole genome sequences of RVA strains circulating in Benin described genetic point mutations and reassortment events as well as novel alleles. Further detailed studies on these new alleles are needed and these data can also provide a baseline for studies on RVA in the post-vaccination period.

Variation of Secondary Metabolite Contents and Activities against Bovine Diarrheal Pathogens among Zygophyllaceae Species in Benin and Implications for Conservation.

Balanites aegyptiaca is a wild plant species largely used in folk medicine and a priority fruit tree in West Africa. In Benin, its overexploitation for ethnoveterinary uses could lead to its rarity or extinction in the long term. In this study, we evaluate the possibilities of its substitution by other Zygophyllaceae species. This study was based on optimal defense theory, which distinguished 2 categories of plants: K-strategist species and r-strategist species. Phytochemical screening was carried out based on aqueous extracts of the leafy stems of B. aegyptiaca and Guaiacum officinale (K-strategist species) and Tribulus terrestris and Kallstroemia pubescens (r-strategist species) for the identification of chemical compounds. The phenolic compounds were quantified by quercetin and vanillin methods. The extracts were tested against 5 bacterial strains responsible for severe diarrhea in bovines. Our results indicated the presence of many phytochemicals, such as alkaloids, flavonoids, saponosides, and tannins. The diversity in secondary metabolites is higher for r-strategist than K-strategist species. The contents of total polyphenols ranged from 4.82 ± 0.05 to 41.84 mg GAE/g of extract. The flavonoid contents varied from 30.64 ± 0.35 to 57.11 ± 0.13 mg QE/g of extract and those of the tannins from 0.04 ± 0.00 to 0.06 ± 0.01 mg PE/mL. The sensitivity of the bacterial strains showed a significant dependence on the extracts. Of the species, K. pubescens showed a bactericidal activity on the majority of strains tested and thus could be a potential substitute for B. aegyptiaca in the treatment of infectious diarrhea.

Assessment of the Bacterial Pollution and Detection of Antibiotic Resistance Genes in Benin: Case of the Hydrographic Channel Complex Cotonou-Nokoué Lake.

The study aims to document the level of contamination of the aquatic ecosystem of the Cotonou-Lake Nokoué canal hydrographic complex by multidrug-resistant bacteria and their resistance genes. For this purpose, water samples were taken from several points of the complex and from the sediments at the depth of the lake. Samples of several species of freshly caught fish products from the lake were also collected. Bacteriological analyses were carried out according to the AFNOR standard (NF U: 47-100). The identification of the different bacterial species isolated was then carried out using the API 20E gallery and specific biochemical tests. The antibiogram of the strains was performed according to the recommendations of the EUCAST. Molecular characterization of the identified strains was carried out by searching for resistance and virulence genes. The results obtained revealed the presence of several bacterial species in water samples and in sediment and intestine samples of fishery products with a predominance of Gram-negative bacilli. The resistance profile of Gram-negative bacilli showed a total resistance to metronidazole (100%). 23% of the strains were also resistant to ciprofloxacin, 41% to amoxicillin, and 60% to aztreonam. Of the Gram-positive cocci identified, 66% was resistant to vancomycin, 7.5% to ciprofloxacin, 71% to erythromycin, and 22% to tetracycline. Regarding the genes sought, bla TEM (46%), bla SHV (24%), and bla CTX-M-15 (31%) were present in the genome of Gram-negative bacilli as resistance genes and fimH (41%) as virulence gene. As for Gram-positive cocci, the van B gene was completely absent. The van A was present at 6.25% in Staphylococcus aureus and mecA at 21.88 and 33.33%, respectively, in Staphylococcus aureus and coagulase-negative staphylococci strains. The high resistance of isolated bacterial strains is a matter of concern and calls for a rational use of antibiotics in order to avoid the transmission of antibiotic resistance from the environment to humans.

Molecular characteristics of rotavirus genotypes circulating in the south of Benin, 2016-2018.

OBJECTIVE: Rotavirus remains the main causative agent of gastroenteritis in young children in countries that have not yet introduced the vaccine. In Benin, rotavirus vaccine was introduced late December 2019 into the EPI. This study aims to provide pre-vaccination era rotavirus genotyping data in Benin. These data can supplement data from the surveillance system of Ministry of Health of Benin which is supported by the World Health Organization (WHO). RESULTS: Of the 420 diarrheal stool samples, actively collected in southern Benin from July 2016 through November 2018 from children under 5 years old and suffering from gastroenteritis, 167 (39.8%) samples were rotavirus EIA positive. 186 (44.3%) samples contained amplifiable rotavirus RNA detected by qRT-PCR method and were genotyped using one-step RT-PCR multiplex genotyping method. G1P[8] represents the predominant genotype (32%) followed by the G2P[4] (26%), G3P[6] (16%), G12P[8] (13%) and mixed G and P types (1%). Four samples (2%) could not be assigned both G and P type specificity.

Prevalence and susceptibility to antibiotics from Campylobacter jejuni and Campylobacter coli isolated from chicken meat in southern Benin, West Africa.

OBJECTIVE: Poultry is commonly considered to be the primary vehicle for Campylobacter infection in humans. The aim of this study is to assess the risk of Campylobacteriosis in chicken meat consumers in southern Benin by assessing the prevalence and resistance profile of Campylobacter coli and Campylobacter jejuni isolated from chicken thigh in Southern Benin. RESULTS: The contamination rate of Campylobacter in the samples was 32.8%. From this percentage, 59.5% were local chicken thighs and 40.5% of imported chicken thighs (p = 0.045). After molecular identification, on the 256 samples analyzed, the prevalence of C. jejuni was 23.4% and 7.8% for C. coli, with a concordance of 0.693 (Kappa coefficient of concordance) with the results from phenotypic identification. Seventy-two-point seven percent of Campylobacter strains were resistant to Ciprofloxacin, 71.4% were resistant to Ampicillin and Tetracycline. 55.8% of the strains were multi-drug resistant.

Healthcare-associated infections: bacteriological characterization of the hospital surfaces in the University Hospital of Abomey-Calavi/so-ava in South Benin (West Africa).

BACKGROUND: Healthcare-associated infections have become a public health problem, creating a new burden on medical care in hospitals. The emergence of multidrug-resistant bacteria poses a difficult task for physicians, who have limited therapeutic options. The dissemination of pathogens depends on "reservoirs", the different transmission pathways of the infectious agents and the factors favouring them. Contaminated environmental surfaces are an important potential reservoir for the transmission of many healthcare-associated pathogens. Pathogens can survive or persist in the environment for months and be a source of infection transmission when appropriate hygiene and disinfection procedures are inefficient. The aim of this study was to identify bacterial species from hospital surfaces in order to effectively prevent healthcare-associated infections. METHODS: Samples were taken from surfaces at the University Hospital of Abomey-Calavi/So-Ava in South Benin (West Africa). To achieve the objective of this study, 160 swab samples of hospital surfaces were taken as recommended by the International Organization for Standardization (ISO 14698-1). These samples were analysed in the bacteriology section of the National Laboratory for Biomedical Analysis. All statistical analyses were performed using SPSS Statistics 21 software. A Chi Square Test was used to test the association between the Results of culture samples and different care units. RESULTS: Of the 160 surface samples, 65% were positive for bacteria. The frequency of isolation was predominant in Paediatrics (87.5%). The positive samples were 64.2% Gram-positive bacteria and 35.8% of Gram-negative bacteria. Staphylococcus aureus predominated (27.3%), followed by Bacillus spp. (23.3%). The proportion of other microorganisms was negligible. S. aureus and Staphylococcus spp. were present in all care units. There was a statistically significant association between the Results of culture samples and different care units (χ2 = 12.732; p = 0.048). CONCLUSION: The bacteria found on the surfaces of the University Hospital of Abomey-Calavi/So-Ava's care environment suggest a risk of healthcare-associated infections. Adequate hospital hygiene measures are required. Patient safety in this environment must become a training priority for all caregivers.

In vitro assessment of antibacterial activity from Lactobacillus spp. strains against virulent Salmonella species isolated from slaughter animals in Benin.

BACKGROUND AND AIM: Salmonella spp. are among the world's leading foodborne pathogens, found naturally in the intestines of many animals. Lactic acid bacteria, mainly Lactobacillus, are a promising alternative to antibiotics for animal and human health. This study aimed to assess the in vitro antibacterial activity of Lactobacillus spp. strains against virulent Salmonella spp. isolated from slaughter animals in Benin. MATERIALS AND METHODS: Eleven samples of raw cow's milk, five samples of breast milk, and six infant stool samples were taken. From these samples, strains of Lactobacillus were isolated and identified. The probiotic potential of each of the identified strains was characterized, and finally in vitro antibacterial activity of these strains was evaluated against three virulent strains of Salmonella spp. and a reference strain of Salmonella Typhimurium ATCC 14028. RESULTS: Out of the 22 samples collected, 20 strains of Lactobacillus spp. were isolated and identified. These strains included Lactobacillus plantarum (30%), Lactobacillus delbrueckii (25%), Lactobacillus casei (25%), Lactobacillus salivarius (15%), and Lactobacillus acidophilus (05%). Characterization of the probiotic potential of these strains showed that only 16 strains were resistant to pH=1.5. Fourteen of them were able to withstand the simulated gastric juice (pH 1.5+pepsin). The 14 probiotic strains showed very good antibacterial activity against virulent strains of Salmonella spp. with inhibition zone diameters ranging from 12.36±0.03 mm to 35.33±0.05 mm (R values>6 mm). CONCLUSION: From this study, Lactobacillus strains isolated from raw cow milk, breast milk, and infantile stool might be used as some valid candidates for probiotics. It also represents good alternatives for antibiotics in the fight against animal and human salmonellosis.

Epidemiological Survey of Rotaviruses Responsible for Infantile Diarrhea by the Immunomolecular Technique in Cotonou (Benin, West Africa).

Rotavirus remains the main causative agent of gastroenteritis in young children, in countries that have not yet introduced the vaccine. Benin, in order to implement the WHO recommendations, projects to introduce the rotavirus vaccine in 2018 as part of its Expanded Program on Immunization. But before the introduction of this vaccine, epidemiological data on rotavirus infections and rotavirus genotypes circulating in Benin should be available. The aim of this study is to generate epidemiological data on infantile rotavirus diarrhea in Benin. In order to determine the epidemiological characteristics and electrophoretypes of rotavirus responsible for gastroenteritis in diarrheic children aged 0 to 5 years, 186 stool samples were collected according to the WHO Rotavirus Laboratory Manual from March 2014 to February 2015 at Suru-Lere University Hospital Center. Detection of rotavirus antigen was performed by the ELISA test, followed by molecular characterization using polyacrylamide gel electrophoresis. 186 stool samples were analyzed for rotavirus, and seventy-three (39.2%) were found to be positive for rotavirus antigen by ELISA. Children aged 3 to 24 months were the most affected by rotavirus diarrhea in this study. Of the seventy-three children affected with rotavirus diarrhea, 27 (37%) had vomiting accompanied by dehydration and fever. Results based on electrophoresis showed that, among the 73 samples tested, 38 yielded typical rotavirus electrophoretic migration profiles.