Tiger Brands announced on Monday that "low levels" of listeria had been detected at its plant in Pretoria.

"Tiger Brands has taken the precautionary measure of closing the factory and has instituted a product recall of all Snax products manufactured at the Pretoria factory with immediate effect," the company said in a statement.

In addition, the company said it would send samples for genome sequencing to establish the specific strain of listeria.

At least 183 people have died in an outbreak of the food-borne disease and 978 cases have been reported since January 2017.

On March 4, Health Minister Aaron Motsoaledi announced that an investigation into the outbreak had traced the ST6 strain of the listeria bacteria, believed to be behind the outbreak, to Tiger Brands' Enterprise factory in the Limpopo capital of Polokwane.

The factory has since been closed.

Tiger Brands CEO Lawrence MacDougall said at the time that the company's Polokwane, Germiston and Pretoria factories were undergoing "an extensive deep clean" of all equipment and machinery and that structural upgrades to the facilities were being carried out.

This was to ensure that the facilities "exceed the highest, best practice standards for meat processing facilities", MacDougall said.

Three law firms are pursuing Tiger Brands in two separate class actions.

MacDougall was however adamant that there was no direct link between the company and the deaths.

"At Tiger Brands, we promised our stakeholders that we will not compromise on quality, safety and internal controls.

"During this period of investigation and discovery we have decided to be extra cautious and to take immediate precautionary action when traces of listeria are detected where they are not expected," he said.