Short communication: Antibiotic resistance in Gram-negative bacteria isolated from street-vended foods in Bangladesh

Antibiotic-resistant pathogens disseminated through food are a public health concern. Although a significant proportion of the urban population in developing countries consume street-vended foods, their role in spreading antibiotic resistance has been rarely investigated. In this study, we evaluated the antibiotic resistance patterns of bacterial isolates (n = 50) collected from five categories of street-vended foods (phuchka, chatpati, sausage, bun, and salad) in Bangladesh. Antibiotic susceptibility to twelve antibiotics was investigated by the Kirby-Bauer disk diffusion method. We found a high prevalence of E. coli (n = 32) in street-vended foods, with most isolates (65.63%) exhibiting multidrug resistance. The multiple antibiotic resistance (MAR) index showed that 22 isolates had MAR above 0.2, with resistance mostly against oxacillin, ampicillin, and cefuroxime. From the rest, three representative isolates were selected for molecular identification by DNA sequencing of 16S rDNA. Klebsiella oxytoca showed multiple drug resistance (MDR) and was resistant to ampicillin, oxacillin, cefuroxime, and kanamycin. Burkholderia fungorum showed no distinct inhibition zone against ampicillin and chloramphenicol. Additionally, the Serratia nematodiphila isolate showed no distinct inhibition zone against three antibiotics, including ampicillin, oxacillin, and cefuroxime. These findings might contribute to the knowledge of emerging antibiotic-resistant foodborne pathogens and raise concerns about the safety of street-vended foods in Bangladesh.