According to the researchers, "However, it is essential for retailing outlets to adhere to hygienic principles when handling and processing pork and chicken meat products to reduce the potential risk of microbial contamination," the scientists said.
This study revealed that the resistance to essential classes of antibiotics, such as cephalosporins, aminoglycosides, and fluoroquinolones, is not high; however, an analysis of similar data showed that resistance might be increasing over time.
Their analysis also shows worrying levels of resistance to tetracycline and penicillin, two of the most commonly used antibiotics in animal agriculture, demonstrating the necessity of responsible antibiotic use.
With new resistance mechanisms emerging and spreading globally, the scientists pointed out that there is a need for a concerted effort to gain insights on how to better tackle AMR as well as raise awareness.
Some of the results of this investigation give an excellent glimpse of the levels of bacterial carriage in chicken and poultry meat sold at major supermarkets across Kenya.
The study noted a high prevalence of bacteria often considered parasitic, such as E. coli at 48.4 per cent and Klebsiella spp at 19.1 per cent, and foodborne pathogens, such as Salmonella spp at 17.8 per cent and Staphylococcus spp at 6.7 per cent.
Though there was a potential for cross-contamination in the fridge/freezer shelves through liquid drips from one food item to another, the study suggests that there was a likelihood of this happening because the samples were found to be shrink-wrapped in polymer plastic film bags at the time of sampling.
"Therefore, the reported bacterial contamination of pork and chicken meat might have its origins at the farm level during the slaughtering process or packaging," the study suggests.
The contamination could also be through extensive use of antibiotics for prevention and growth promotion in chickens and pigs has been a major factor in the development of antimicrobial resistance in bacteria with zoonotic potential, which is a serious public health issue.
The leading supermarkets in Kenya are concentrated in cities - Nairobi, Kisumu, Mombasa, and Nakuru - and other big towns such as Eldoret and Naivasha.
The authors explained that this is because urbanisation has created an easily accessible market for them in addition to improved infrastructure that facilitates transportation and storing of the perishable animal-sourced foods in their outlets.
At the time of conducting the study, publicly available information showed that 89 per cent of the international supermarket outlets and over a third of regional supermarket outlets were in Nairobi with a population of over 4 million people as reported in the 2019 national census.
Nearly 98.4 per cent - 184/187 - of pork and 96.6 per cent - 199/206 - of poultry samples tested revealed the presence of at least one type of bacterium.
In total, 611 bacterial isolates were recovered from the analysis of the 393 pork and poultry samples, but only 551 isolates were processed further depending on the resource availability.
All the samples were purchased either as wrapped/sealed by the supplier or repackaged by the outlet, within their expiry date, and the product branding was covered to blind the laboratory personnel.
The samples were then transported in coolers to the Kenya Medical Research Institute within five hours, where processing began immediately. Moreover, data on the freshness of the sample, packaging method, storage temperature, and the type of PPE worn by the supermarket attendant was also collected.
Laboratory tests were carried out to detect foodborne bacteria in poultry meat and pork samples. Enrichment strategies and media were chosen carefully to enable the growth of non-fastidious bacteria.