The results of research that was conducted in 2019–2020 to investigate the prevalence of the food-borne pathogen Listeria monocytogenes in beef and beef products at certain abattoirs and retailers in the provinces of Gauteng, Mpumalanga, and the North West generated findings that might have potentially serious consequences for consumers.
A study that was carried out by the University of Pretoria’s Faculty of Veterinary Science and the Agricultural Research Council-Onderstepoort Veterinary Institute (ARC-OVI) found that 4.6% of cold carcasses sampled at seven abattoirs in one of the provinces were found to be contaminated with Listeria monocytogenes. The research was based on a study carried out in 2014. This suggests that beef and products connected to cattle sold at retail locations in the province may contain contaminated carcasses and, as a result, may make their way into the food chain.
The epidemic of listeriosis in 2017–2018, which resulted in 1,065 confirmed cases and 218 deaths, served as the motivation for the research, which Red Meat Research and Development South Africa financed. The study was conducted in South Africa.
“Processed foods become contaminated by contact with equipment, the handling of raw products, or from post-processing settings in which the pathogen can survive despite the routine use of disinfectants,” said Dr Rebone Moerane, Head of UP’s Department of Production Animal Studies, who was part of the research team along with Professor Abiodun Adesiyun, an extraordinary professor in the department, Dr Nomakorinte Gcebe of the ARC-OVI, and four postgraduate students.
Researchers from the University of Pretoria looked at the prevalence of Listeria as well as the causes that put it there in cattle, hay, feeds, and water on farms in the three provinces, as well as in dead animals and carcasses at processing plants, and contaminated beef products sold in retail stores. Samples of raw beef and beef products, including ready-to-eat commodities, were collected from shops of varying sizes. Additionally, swabs of carcasses were obtained from slaughterhouses, and samples from cattle ranches were collected.
According to the study findings, there is a very low risk of listeriosis infection for cattle kept on farms. They did remark, however, that it is concerning to identify contaminated chilled carcasses at abattoirs in Gauteng in addition to the discoveries that were made at retail shops.
The incidence of Listeria was found to be 6%, 8.3%, and 9.3%, respectively, in beef and beef products sampled at retail establishments in North West, Mpumalanga, and Gauteng. The frequency was 4.3%, 11%, and 9.3% for cold meat and goods made with beef, respectively.
“Some of the goods that were infected were ready-to-eat foods, such as polony, which many people and biltong enjoy. According to Moerane, this raises the probability that humans will come into contact with the infectious agent.
Abattoirs and processing facilities should be subject to stringent food safety standards to reduce the risk of contamination and the chance of a fresh listeriosis epidemic, according to experts’ recommendations to both the government and the private sector.
In pregnant women, listeriosis is a disease that has a risk of death and may lead to complications such as miscarriage and stillbirth. The vast majority of human cases are connected to the consumption of prepared meals, and the likelihood of contracting the illness increases in proportion to the amount of food eaten. The pathogen can survive and thrive in the chilled temperatures used to store products to prevent them from decomposing.
