Alarm bells sounded as University of Pretoria study reveals concerning findings on Listeria in beef.
A recent investigation by the University of Pretoria (UP) has unveiled alarming results regarding the presence of the food-borne pathogen, listeria monocytogenes, in beef and its products across Gauteng, Mpumalanga, and North West provinces.
The study, spearheaded by UP's Faculty of Veterinary Science in collaboration with the Agricultural Research Council-Onderstepoort Veterinary Institute, found that 4.6% of chilled carcasses from seven abattoirs in one province tested positive for listeria.
This suggests that tainted beef could potentially find its way to consumers via retail outlets.
Listeria monocytogenes is notorious for causing listeriosis, a severe ailment that can lead to miscarriages and stillbirths in pregnant women.
The majority of human infections stem from consuming ready-to-eat foods.
Alarmingly, the pathogen thrives even in refrigerated conditions, typically used to deter spoilage.
Dr Rebone Moerane, head of UP’s Department of Production Animal Studies, highlighted the risks, stating, “Processed foods can be contaminated through various means, including contact with equipment, handling of raw ingredients, or even in post-processing environments where the bacteria can persist despite regular disinfection.”
Moerane further emphasised the risks associated with slaughter, noting that a range of foods, from beef to dairy products, can be carriers of the pathogen, leading to outbreaks among consumers.
The research initiative was funded by Red Meat Research and Development South Africa, triggered by the 2017-2018 listeriosis outbreak in South Africa.
This outbreak saw over 1,000 confirmed cases and approximately 216 fatalities.
Processed foods, especially polony, were believed to be the primary culprits.
Speaking on eNCA Moerane said the finding of the study indicated that there were serious challenges and that “we really need to take actions and interventions”.
He said that part of the problem was that country’s legislation in terms of its meat laws were fragmented.
“Because if you look at the need in terms of abattoirs, the veterinary services are under the Department of Agriculture who are responsible in ensuring that there is monitoring of our abattoirs and ensuring the are following the right process in the production of meat at the end.
“By the time the meat leaves the abattoirs, then it becomes the responsibility of health and particularly municipalities,” he said.
He, however, said that he was confident that the Department of Agriculture and the red meat industry were implementing measures to ensure that abattoirs are hygienic and there are monitoring programmes to ensure they reduce the risk in abattoirs.
“Our biggest concern is more at retailer level. What is happening we don't have a clue. Are municipalities implementing the right measures in doing proper inspection? And surveillance monitoring? That is of concern,” he said.
Professor Abiodun Adesiyun, a professor in the department, elaborated on the study's objectives, saying, “Our aim was to discern the prevalence and molecular characterisation of pathogenic serotypes of listeria in beef across the three provinces.”
The comprehensive study also explored the prevalence of the pathogen in various stages of beef production. This included examining cattle, their feed, and water sources on farms; analysing slaughtered cattle and carcasses at processing facilities; and assessing the contamination levels in beef products at retail stores.
The research methodology was exhaustive. Samples were collected from cattle farms, including faeces, feed, silage, and water. Additionally, swabs from carcasses at abattoirs and samples from retail beef products were analysed.
Worryingly, some detected serotypes of listeria monocytogenes were from groups known to cause human listeriosis. The frequency of virulence genes, indicators of the pathogen's ability to cause disease, varied across provinces, but reached alarming levels in some areas.
This study underscores the critical need for stringent safety measures across the beef production chain to safeguard public health.