Hospital wastewater is a recognized reservoir for resistant Gram-negative bacteria. This study aimed to screen for carbapenemase-producing Escherichia coli and Klebsiella pneumoniae and their resistance determinants in two hospital effluents of Ouagadougou. Carbapenem-resistant E. coli and K. pneumoniae were selectively isolated from wastewater collected from two public hospitals in Ouagadougou, Burkina Faso. Bacterial species were identified via MALDI-TOF mass spectrometry. Carbapenemase production was studied phenotypically using antibiotic susceptibility testing via the disk diffusion method. The presence of carbapenemases was further characterized by PCR. A total of 14 E. coli (13.59%) and 19 K. pneumoniae (17.92%) carbapenemase-producing isolates were identified with different distributions. They were, respectively, bla_NDM (71.43%), bla_VIM (42.86%), bla_IMP (28.57%), bla_KPC (14.29%), bla_OXA-48 (14.29%); and bla_KPC (68.42%), bla_NDM (68.42%), bla_IMP (10.53%), bla_VIM (10.53%), and bla_OXA-48 (5.26%). In addition, eight (57.14%) E. coli and eleven (57.89%) K. pneumoniae isolates exhibited more than one carbapenemase, KPC and NDM being the most prevalent combination. Our results highlight the presence of clinically relevant carbapenemase-producing isolates in hospital effluents, suggesting their presence also in hospitals. Their spread into the environment via hospital effluents calls for intensive antimicrobial resistance (AMR) surveillance.

Antimicrobial resistance (AMR) is a global public health threat. Quality data are needed to address the rise of multidrug-resistant clones, particularly in sub-Saharan Africa. In this study, we analysed the prevalence, antimicrobial resistance profile, and presence of genes encoding extended-spectrum β-lactamase-producing Escherichia coli (ESBL-Ec) and Klebsiella pneumoniae (ESBL-Kp) in environmental samples from Ouagadougou, Burkina Faso. Of 264 samples collected, 95 (36%) and 74 (28%) contained ESBL-Kp and ESBL-Ec, respectively. ESBL-Kp was more prevalent in runoff water and in treated and untreated wastewater, while ESBL-Ec was more prevalent in manure. Interestingly, wastewater treatment did not significantly reduce the recovery of ESBL bacteria. As expected, resistance to third- and fourth-generation cephalosporins was predominant, and rare for second generation cefoxitin. Interestingly, all the isolates from treated wastewater were susceptible to ampicillin and piperacillin, while all the other clones were resistant to these antibiotics. Regarding the ESBL-encoding genes, the bla_CTX-M family was the most abundant, with the bla_CTX-M1 subfamily being the most prevalent. Carriage of combinations of ESBL genes was common, with the majority of the isolates harbouring 2–4 different genes. This study highlights the need for active surveillance to manage the risk of exposure to ESBL bacteria in Burkina Faso.

Urinary tract infection (UTI) is a common patient infection and a major public health problem today. The rapid spread of antibiotic resistance genes in Enterobacterales, particularly in Extended-spectrum beta-lactamases producing Escherichia coli (ESBL-E. coli), is compromising treatment with the antibiotics that are normally used. The aim of this study was to evaluate the level of susceptibility of uropathogenic ESBL-producing E. coli to fosfomycin as an alternative treatment. A total of 3369 samples of urine were received and processed in the Bacteriology Laboratory of the Niamey General Reference Hospital (NGRH) throughout 2021. Synergy testing was performed for phenotypic detection of ESBLs, and fosfomycin sensibility of ESBLs-producing uropathogenic E. coli isolates were determined using the Viteck-2 system. Of the 280 enterobacteria identified in the urine samples, 104 Escherichia coli isolates were positive to the synergy test. The average age of the patients was 54 ± 17. The age range of 46–65 years was the most affected by these infections. The female patients predominated over the male ones, with a prevalence of 51.90%, a sex ratio of 1.08. The ESBL-producing E. coli isolates were 0.97% resistant to fosfomycin. Fosfomycin is highly effective against uropathogenic ESBL-producing E. coli isolates. It could be used as an alternative treatment for both uncomplicated and complicated urinary tract infections.

Background: Salmonella spp. are leading causes of gastroenteritis and typhoid fever worldwide, with hospital-acquired infections posing significant clinical challenges. The emergence of antibiotic resistance among clinical isolates has been increasingly recognized as a major contributor to treatment failure in affected patients. Objective: This study aimed to determine the prevalence and antimicrobial resistance patterns of Salmonella spp. isolated from clinical specimens at the National Hospital of Niamey, Niger. Method: Stool and blood samples were collected from patients presenting with clinical signs of enteric fever or gastroenteritis. Salmonella spp. was identified via standard microbiological methods, and antimicrobial susceptibility testing was performed via the disk diffusion method on Mueller‒Hinton agar in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Extended-spectrum beta-lactamase (ESBL) production was confirmed by a double-disk synergy test, which assessed the enhancement of inhibition zones between amoxicillin/clavulanic acid and third-generation cephalosporins. Results: Seventy-seven Salmonella isolates were recovered, yielding an overall prevalence of 2.55%. The majority of the isolates (80.52%) were obtained from children under 5 years of age. High resistance rates were observed against amoxicillin and amoxicillin/clavulanic acid (79% each). Multidrug resistance (resistance to ≥3 antibiotic classes) was detected in 25.97% of the isolates, whereas 35% were resistant to at least two antibiotics. Notably, 5.19% of the isolates were confirmed as ESBL-producing strains. Conclusion: These findings highlight the significant burden of multidrug-resistant Salmonella spp., including ESBL producers, in the clinical setting of Niamey. The high prevalence of resistance to commonly used antibiotics underscores the urgent need for enhanced antimicrobial resistance surveillance, rational antibiotic use, and infection control strategies to curb the spread of resistant strains in healthcare and community environments.