Prevalence and risk of staphylococcal and coliform carcass contamination of chickens slaughtered in the informal market in Gauteng, South Africa

Abstract

PurposeThe primary objective was to determine the prevalence of indicator microorganisms [Staphylococcus aureus, non-S. aureus staphylococci (NSAS), coliforms and aerobic bacteria] for contamination of chicken carcasses, carcass drip and rinse water from the informal chicken market in Gauteng, South Africa.Design/methodology/approachChicken swabs, chicken drips and rinse waters were collected from 151 chickens from 47 random outlets. Pre-tested questionnaires were administered to capture the risk factors for bacterial contamination. Standard microbiological procedures were conducted for isolation and enumeration of target bacteria.FindingsNSAS (64% and 41%) and S. aureus (12% and 31%) were prevalent on carcasses and in carcass drip respectively. Coliforms (62%) and aerobic bacteria (85%) were detected in rinse water. Significant risk factors for contamination of carcasses with NSAS, S. aureus and coliform organisms were: evisceration of chickens on the same location used for sale, cleaning of display counter with dirty clothes/wipes, holding of differently sourced chickens in the same cage prior to slaughter, not cleaning the display table/counter and hands at all, washing knives in rinse water, high turnover of daily slaughter and length of time to display chickens.Research limitations/implicationsThe limitations of this research were the limited geographical coverage and small sample size.Practical implicationsThe isolation of these indicator microorganisms suggests the potential presence of other chicken-borne pathogens not tested for in the study.Social implicationsThe findings serve to inform policy on public health and street-vended food and can guide control on good sanitary practices.Originality/valueThis is the first comprehensive report on ready to eat chickens from the informal markets in Gauteng, South Africa.

Antimicrobial Resistance Profiles of Salmonella Isolates on Chickens Processed and Retailed at Outlets of the Informal Market in Gauteng Province, South Africa

“…Of the 170 Salmonella isolates recovered from carcass swabs, cloacal swabs and carcass drips, all (100%) exhibited resistance to antimicrobial agents. This study strategy was used because of the unique situation in ‘wet markets’, such as the informal market outlets in Gauteng province which have limited physical infrastructure, lack a potable water supply, have poor drainage, and inadequate wastewater and solid waste disposal [ 25 ]. Most importantly, as reported earlier [ 25 ], slaughtered chickens are rinsed in infrequently changed water in drums and buckets.…”

“…This study strategy was used because of the unique situation in ‘wet markets’, such as the informal market outlets in Gauteng province which have limited physical infrastructure, lack a potable water supply, have poor drainage, and inadequate wastewater and solid waste disposal [ 25 ]. Most importantly, as reported earlier [ 25 ], slaughtered chickens are rinsed in infrequently changed water in drums and buckets. The implication is that there is a high potential for cross-contamination among several carcasses with resistant Salmonella during the rinsing process.…”

“…To select outlets of the informal market for the study, different categories of outlets identified during the preliminary visits were used. The criteria used for the number of samples collected from each outlet and township, and from each selected outlet were described earlier [ 22 , 25 ]. The types of chickens sampled at the outlets included culled breeders, spent chickens, and broilers which originated from both large commercial and Developing Poultry Farmers Organization (DPFO), as well as from backyard farms in Gauteng province.…”

“…The protocol used for the isolation and identification of Salmonella from chicken swabs, cloacal swabs and carcass drips was earlier described [ 14 , 25 , 32 ]. Briefly, each of the 151 chicken samples were inoculated into two enrichment broths, Rappaport Vassiliadis Soya (RVS) broth and Mueller–Kauffman tetrathionate (MKTT) broth and incubated for 24 h at 41.5 and 37 °C, respectively.…”

“…Furthermore, their prices are competitive and affordable, and they are conveniently located [ 22 , 23 , 24 ]. However, since these outlets are unregulated by health personnel and are considered illegal, concerns have been raised regarding their roadside locations, lack or inadequacy of potable water, and inadequate wastewater and solid waste disposal [ 22 , 25 , 26 ]. Sanitary practices have been reported to be poor, posing health risk to consumers of products from these outlets [ 22 , 23 , 27 ].…”