Listeria in South Africa: Lessons Learned
As many in the food safety community know, the largest outbreak of foodborne illness on the planet took place last year in South Africa, with 1,053 cases and 212 deaths due to consumption of Ready-to-Eat meat products contaminated with Listeria monocytogenes, strain ST61. Needless to say, the human toll has been enormous, and those who lived through it will never be the same. If you’re like me, you may have wondered, “how did this happen?”, and “could this happen in the U.S.?” To answer these questions, we first need to understand that outbreaks happen due to several factors. Among these are the failure to control a foodborne hazard at the plant level, failure to recognize there has been a lack of control, failure to recognize the hazard has caused an outbreak of foodborne illness, failure to respond to the outbreak quickly enough, or a combination of all four. So, what happened in South Africa? Let us explore the situation.
First, we should understand that like in the U.S., the regulatory systems in South Africa are under the jurisdiction of several governmental agencies. However, unlike the U.S., the division of duties among those agencies is quite different. For example, the South African Department of Health (DOH) is responsible for the overall coordination, policy development, and auditing of the national food safety control program, and of serving as the international liaison for the government to develop regulations for importers and exporters2. Enforcement activities of the national food safety control program in South Africa (i.e. food inspections) are carried out by 52 local authorities. Therefore, the DOH does not inspect food processing establishments, but rather conducts periodic audits of inspectors who work for local authorities. The Department of Agriculture, Forestry and Fisheries (DAFF) inspects agricultural products for the presence of insects and pests, and plant and animal diseases, not for food safety3. As you can imagine, for this approach to successfully protect public health, it depends heavily on the timely and robust audits of the local authorities and on the proper training of inspectors to ensure that food inspections are carried out well and uniformly in every locality. Finally, in the event of an outbreak of foodborne illness, the National Consumer Commission has authority under Section 60(2) of the country’s Consumer Protection Act to require food manufacturers to conduct an investigation, and if necessary, to recall product from the market4.
It is believed that the South Africa listeriosis outbreak began in early 2017, yet an increase in laboratory-confirmed cases was not reported to the National Institute for Communicable Diseases (NICD) until July of that year5. Moreover, it took until December of 2017 for the outbreak to be officially declared by the Minister of Health, and the product in question was not identified, or a recall order issued, until March of 20186. In an attempt at explaining why it took so long to recognize an outbreak was in progress, and to traceback the product responsible, the DOH declared that “the meat processing industry was not cooperating for months. They did not bring the samples we requested”7. This implies that in the event of an outbreak, the DOH passively waits for industry to inform them and to provide samples. For his part, the CEO of the company responsible (Tiger Brands), Mr. Lawrence McDougall, stated that there was no direct link between the deaths and its cold meat products, therefore they did not contact the authorities8. Clearly something is very wrong with a food safety system if the responsible government agency is unable to identify the source of an outbreak for months, and if it waits for industry to provide samples. To make matters worse, in a news report by Sowetan Live broadcast on March 7, 2018, it was disclosed that regulatory agencies had not yet decided who would conduct further investigations into the outbreak, the National Consumer Commission, the DOH, or the DAFF9. Clearly something continued to go very wrong when the government was unable to decide who would be in charge during what was clearly a public health emergency!
But even before the outbreak began, why did controls fail to prevent it? The answer lies in the fact that South African regulation #692 does not require HACCP in meat processing plants10. In addition, there is only a voluntary guideline (#885) suggesting limits for the presence of Listeria in Ready-to-Eat foods, so it is not enforceable11. In the U.S., the Pathogen Reduction Hazard Analysis Critical Control Points regulation, published by USDA-FSIS in 1996, requires HACCP in every meat and poultry product facility12. As history has shown, this regulation resulted in a significant reduction in the number of positive product samples for this pathogen, from 2.91% in 1997, to 1.03% in 200213. But would having a similar regulation in South Africa, instead of #692, have prevented the massive outbreak? As we know, unfortunately, requiring HACCP was not sufficient to prevent a major outbreak of listeriosis in the U.S. in 1998, which resulted in 101 illnesses and 21 deaths attributed to product sold by Bil Mar Foods, or a second outbreak in 2000 attributed to product from Cargill, resulting in 29 illnesses and 4 deaths. Moreover, while the USDA-FSIS was engaging in a risk assessment of Ready-to-Eat products to determine the best way to minimize the risk of contamination as much as possible, a third major outbreak of listeriosis in Ready-to-Eat meats took place in 2002. This time, there were 54 illnesses and 8 deaths14.
So, as good as requiring HACCP would have been, it probably would not have been enough to completely prevent the South African outbreak. What else would have helped? Certainly, having a zero tolerance for the presence of L. monocytogenes in Ready-to-Eat foods, as we do in the U.S., is a good place to start. More importantly, and going back in our history with this pathogen, the risk assessment commissioned by FSIS mentioned earlier demonstrated that the most effective way to reduce the risk of contamination with Listeria would be to apply a post-processing treatment to the product to ensure that if contamination occurred after cooking (i.e. at the peeling and packaging stage), it would also be eliminated. On June 6, 2003, USDA-FSIS published a new regulation, “Control of Listeria monocytogenes in Ready-to-Eat Meat and Poultry Products” (68 FR 34208). It provided the industry with three alternatives to choose from for controlling this pathogen: (1) the use of a post-processing treatment and an antimicrobial agent or process, (2) the use of a post-processing treatment OR antimicrobial agent or process, or (3) implementation of an increased sanitation and testing program that would test product, food contact surfaces, and the plant environment for the presence of Listeria, and if found, would require that product be reprocessed or discarded, and that the plant environment be thoroughly cleaned and sanitized. Importantly, the regulation specified that if a post-processing treatment was used, then no testing would be required other than as a verification step as part of the establishment’s HACCP plan.
This approach was science-based in that it shifted attention from over-reliance on testing as proof of safety, and towards the use of post-processing treatments designed to reduce, if not actually eliminate the contaminant from the product. In addition, it also appealed to the industry, in that it reduced the frequency of testing of end-product that USDA-FSIS inspectors would conduct. As a result, the number of positive samples collected by inspectors decreased dramatically, and as of 2017, the incidence of L. monocytogenes in Ready-to-Eat meat and poultry products is 0.20%13. There is a better than good chance that if a similar regulation existed in South Africa, that at least the number of samples that were contaminated with the pathogen would have been a lot smaller. The only other remaining element is that of inspection. How much did delegating authority to local bodies for enforcement of regulations contribute to the outbreak? After all, inspectors cannot always determine if product is contaminated simply by random testing, given that contamination with pathogens is not homogenously distributed on product. In fact, to what extent was the quality of food inspection a contributing factor, given the absence of a requirement for HACCP implementation?
The massive South African listeriosis outbreak will not soon be forgotten. It affected the lives of thousands of people, many of whom were children and newborns. In retrospect, it is clear that both the country’s food inspection system, as well as its regulations, failed to establish proper controls and failed to assert proper enforcement by the appropriate entities in order to prevent this terrible episode, or at least minimize its scope. Moreover, lack of preparation in handling the outbreak, including confusion as to which agency should be in charge, tells a story that should not be ignored. Now, before we get too comfortable, let us recognize that the U.S. does not have a perfect food safety system either, far from it. However, it would be difficult to imagine this situation taking place here, given our regulations involving meat products, our inspection systems, and our processes for tracing back product and for identifying outbreaks. Having said that, in the past few years, we have lived through several outbreaks of listeriosis in the U.S. involving contaminated produce. So, there is clearly more that needs to be done. One idea is that perhaps it is time to go beyond Good Agricultural Practices and require antimicrobial processes or treatments at the packing house to reduce the risk of foodborne illness from consumption of produce. Of course, that is easier said than done, but we must not give up. As they say in South Africa, Kom ons doen dit!