Microbial Status and Multidrug Resistance Pattern of Pathogenic Bacteria Isolated from Street Food in Dhaka City, Bangladesh

Aims: This study aims to evaluate the microbiological safety in street foods available in Dhaka city, Bangladesh.

Study Design: Seven categories of street foods were collected aseptically in triplicates from 10 locations of the most populous areas of Dhaka city, transported to the microbiology laboratory of Center of Excellence, Primeasia University, Dhaka. The samples were analyzed for microbiological quality.

Place and Duration of Study: The study was carried out in Dhaka city, Bangladesh, between November 2015 to March 2017. The microbiological analysis was done at the microbiology laboratory of the Center for Excellence Laboratory (CEL), Department of Microbiology, Primeasia University, Dhaka-1213, Bangladesh.

Methodology: Ninety street food samples belonging to 7 different categories were collected aseptically from ten different places in Dhaka. All samples were tested according to the standard food analysis methods. Total viable count (TVC), total coliform count (TCC), total Salmonella-Shigella count (TSSC) and total S. aureus count (TSAC) were estimated by using Plate Count agar (PCA), MacConkey agar, Salmonella-Shigella agar and Mannitol Salt agar plates respectively. Kirby-Bauer disc diffusion method on Mueller Hinton agar was used to determine the sensitivity of the isolated strains to commonly prescribed antibiotics.

Results: Fried Aubergine, sugarcane juice, potato balls, peanut, rice cake, sweetened coconut, local salty snacks nimki and chanachur, sesame cookies revealed high total viable count (1011 CFU/gm or /mL) and high total coliform count (109 CFU/g or /mL). Some street foods were found to contain potential pathogens such as Escherichia coli, Staphylococcus aureus, Salmonella spp., Vibrio spp. and Campylobacter spp. Some of the isolates of E. coli, S. aureus and Salmonella isolates were found to be resistant against azithromycin (15 µg), sulphomethoxazole (25 μg), penicillin (10 µg), nalidixic acid (30 µg), vancomycin (30 µg) and tetracycline (30 μg).

Conclusion: This study reveals the presence of pathogenic bacteria in street foods of Dhaka, Bangladesh. Hence, there is a necessity for strict surveillance on microbial safety of street foods. There should be public engagement projects for.public awareness against consumption of low-quality and unhygienic street foods of Dhaka, Bangladesh.