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Methicillin-Resistant Staphylococcus aureus (MRSA) is a ubiquitous public health challenge, with its prevalence in human, animal, and environmental interfaces posing significant concerns. This study aimed to characterize and detect the zoonotic linkages of MRSA within the cow-environment-human interfaces in dairy farms to address the One Health perspective. A comprehensive investigation, involving 636 samples (an equal number of raw milk and cow nasal swab samples, along with varying numbers of human nasal swab and environmental samples), revealed an overall MRSA prevalence of 13.4% (n = 271/636). Notably, environmental samples exhibited the highest prevalence (19.3%), emphasizing the potential role of farm surroundings in MRSA transmission, while the lowest prevalence was found in raw milk at 11.8% (n = 31/263). The prevalence in cow nasal swabs and human nasal swabs was 13.3% (n = 35/263) and 15.1% (n = 8/53), respectively. Multiplex PCR analysis revealed the presence of different Staphylococcal enterotoxin (SEa, SEb, SEc, and SEd), and exfoliative toxin-producing genes (Eta, Etb) within the MRSA isolates underlining their potential to induce public health threats. All MRSA isolates exhibited complete resistance to Oxacillin (100%) and Amoxicillin (100%), while the highest sensitivity was observed for Vancomycin (85.8%). Furthermore, these MRSA strains demonstrated varying degrees of resistance to other commonly used antimicrobial drugs, including Cefoxitin (75.3%), Ceftarolin (71.2%), Sulfamethoxazole-Trimethoprim (63.5%), Ciprofloxacin (60%), and Gentamicin (49.5%). Detection of MRSA in cow, human, and environmental samples within the same farm vicinity highlights the risk of zoonotic transmission of MRSA from cows to humans through environmental interfaces. Phylogenetic analysis of the mecA gene in MRSA isolates from all sources within the same farm revealed a high similarity index (>84%) among them suggesting a shared evolutionary origin. Moreover, the MRSA isolates from milk samples showed a close evolutionary relationship with isolates from Kenya and Brazil, while the isolates from humans and the environment displayed noticeable resemblance to isolates from several Asian countries. The findings emphasize the importance of collaborative efforts under the One Health framework to address this multifaceted issue and ensure the safety of our food supply and public health.

The occurrence of extended-spectrum beta-lactamase (ESBL) producing bacteria is concerning the scientific community since it confers multiple drug resistance (MDR). The study investigated the prevalence of MDR-ESBL-producing Salmonella strains from shrimp in Sylhet region, Bangladesh. A total of 165 shrimp samples were processed from 55 shrimp specimen from different retail shops. The presence of Salmonella was confirmed by standard methods followed by antibiotic susceptibility testing. Isolates exhibiting resistant to third-generation cephalosporin were considered as Salmonella positive isolates which was later proven by the double disc synergy test. Thirty-nine isolates were identified to be Salmonella positive of which eighteen were from seven department stores and twenty-one from the local market. The body parts had the highest rate of positive samples (30.91%), followed by the head (23.63%), and the tail (16.36%). Additionally, isolated Salmonella were resistant to rifampicin and Cefixime but 100% susceptible to co-trimoxazole, ofloxacin, streptomycin, nalidixic acid, and chloramphenicol, while ciprofloxacin showed intermediate resistance. Vancomycin, cephalexin, ampicillin, and colistin, on the other hand, were among the extremely resistant drugs. Finally, while six of the tested isolates demonstrated resistance against the recommended cephalosporin, three of them (7.69%) were Salmonella ESBL positive in the double disc synergy test. The rising incidence of MDR and the developing prevalence of ESBL-positive Salmonella may put a burden on the healthcare system by limiting access to effective antibacterial drugs. [ J Adv Biotechnol Exp Ther 2023; 6(3.000): 686-700]

Escherichia coli is a notorious ubiquitous organism among the foodborne pathogens which can form biofilm leading to the development of antibiotic resistance. We aimed to investigate E. coli isolated from a total of 240 raw beef and ready-to-eat samples obtained from the capital of Bangladesh along with the microbial quality of the samples. The isolates underwent antibiogram profiling in accordance with the Clinical and Laboratory Standards Institute Guideline 2023 and characterized for the presence of antibiotic resistance genes, as well as for phenotypic and genotypic detection of biofilm formation. The average total aerobic counts and specific bacterial counts exceeded the recommended limit by Bangladesh Food Safety Authority. Among the samples, 86 (36%) samples were positive for E. coli. The antibiogram profile depicted diverse resistance patterns with the highest resistance to ampicillin (100%), amoxicillin (81%), ciprofloxacin (71%), and azithromycin (67%). However, vancomycin (64%), meropenem (57%) and aztreonam (51%) were the most sensitive antibiotics to the isolates. The antimicrobial resistance encoding genes blaTEM (72%) and tetA (65%) were the most prevalent where the percentage of blaOXA-1, blaCITM, blaNDM-1, blaCTX-M-2, blaCTX-M, blaCMY, blaCTX-M-1 and blaSHV genes were 42%, 33%, 6%, 20%, 17%, 16%, 14% and 9% respectively. Phenotypic characterization, utilizing Congo red agar and microtiter plate tests, identified 53 out of 86 isolates as biofilm producers, with 10 classified as strong producers, and 8 and 35 as intermediate and weak producers, respectively. Molecular detection methods revealed that among the 53 isolates positive for biofilm production, 96% carried the csgA gene. Additionally, high prevalence rates were observed for fliC (80%), bcsA (66%), and fimH (60%), indicating their significant roles in biofilm formation. Conversely, the prevalence of agn43 was lower, with only 30% of isolates harboring this gene. This study addresses a knowledge gap, highlighting the public health risks associated with biofilm-producing foodborne pathogens and the emergence of antimicrobial resistance, underscoring the necessity for improved hygiene practices to mitigate the public health threats posed by these pathogens.