South African Listeria outbreak traced to RTE processed meat

A total of 948 cases have been reported since January 2017 and 180 of the 659 patients with known outcomes have died. 742 cases were reported in 2017 and 206 this year.

The National Institute for Communicable Diseases (NICD) has interviewed 109 ill people on what they ate in the month before falling ill.

Ninety three (85%) reported eating ready-to-eat (RTE) processed meat products, of which polony (a type of sausage) was the most common followed by viennas/sausages and then other ‘cold meats’.

Avoid processed meats​

Aaron Motsoaledi, health minister, advised the public to avoid processed meat products sold as RTE.

While polony is implicated there is a risk of cross-contamination of other RTE processed meat products at production, distribution or retail.

Listeria on the exterior casing (packaging) can be transferred to other products such as ‘cold meat’ items typically not cooked before eating.

More than 1,500 foodstuffs from retail outlets, processing plants and patient homes have been tested at the NHLS Infection Control Services lab and over 70 items were positive for the pathogen.

From clinical isolates obtained from patients, nine sequence types of L. monocytogenes were isolated but most were sequence type 6 (ST6).

Listeriosis was made a notifiable disease so every diagnosed patient had to be reported.

Link to Enterprise Foods​

L. monocytogenes was isolated from an ill child and samples from two unrelated polony brands made by Enterprise and Rainbow Chicken Limited (RCL) in late January.

The pathogen was found in more than 30% of the environmental samples collected from the Enterprise factory in Polokwane.

Whole genome sequencing at the site confirmed the outbreak strain (ST6) in at least 16 environmental samples.

Preliminary results show that several RTE processed meat products from the plant in Germiston contain L. monocytogenes but the sequence type is not yet known.

Enterprise Foods, a division of Tiger Consumer Brands, said all identified products will be recalled.

“The company proactively amplified its testing for Listeria and can confirm that we had found a low detection of a strain of Listeria in some products on 14 February but the presence of the ST6 strain has not been confirmed by our tests. The company has furthermore sent its samples to an external laboratory to test for the strain itself and should receive the results tomorrow [Monday].” ​

Lawrence MacDougall, CEO at Tiger Brands, said consumer safety remains its highest priority so immediate action is being taken.

“[We] can confirm that we have, with immediate effect, undertaken a full national recall of the affected Enterprise ready-to-eat meat product range. Additionally, we have suspended operations at both Enterprise manufacturing facilities (Polokwane and Germiston) and have halted supply to trade.​

“Since the confirmed outbreak of Listeriosis by the DoH in December 2017, we have amplified our testing for Listeria of both raw materials and finished goods and have also introduced additional hygiene monitoring of our processes, equipment, storage and waste areas at our facilities.”​

RCL investigation ongoing​

Investigation of the RCL Wolwehoek production facility is continuing.

Polony products have tested positive for L. monocytogenes but sequence types are not ST6.

More than 10% of environmental samples collected have tested positive but sequence types are not known as yet.

The opposition political party in the country, the Democratic Alliance (DA), welcomed the news that the source has been traced.

It also backed the move by the National Consumer Commission (NCC) to issue the companies involved with safety recall notices and suspend them from exporting goods temporarily.