Health Minister Dr Aaron Motsoaledi announced on Tuesday morning that while Listeriosis is a serious disease, it can be treated with antibiotics.
The minister further urged the public to keep food at safe temperatures, to wash hands before handling food and often during food preparation and to use safe water for domestic use at all times and use pasteurised milk products.
He said infection with listeria may result in conditions including flu-like illness with diarrhoea, including fever, general body pains, vomiting and weakness, infection of the blood stream which is called septicaemia, and meningoencephalitis [infection of the brain].
"Most cases (62%, or 345 cases) have been reported from Gauteng‚" Motsoaledi said.
It poses a higher risk for newborns, the elderly, pregnant women, and persons with weak immunity, the health department said.
The flag for the latest outbreak was raised in July, when Gauteng doctors from neonatal units at Chris Hani Baragwanath and Steve Biko hospitals recorded an unusually high number of babies with listeria.
Of the 557 cases, the department of health has found the final outcome of 70 confirmed cases of Listeriosis.
The source of the outbreak is now being investigated, but Motsoaledi said it's believe that this particular outbreak is from a food source that is being consumed by both the rich and the poor, and the contamination points may well be farms and food processing plants.
"We are satisfied that the government is now instituting investigations to understand how the outbreak is being transmitted".
People usually contract it through animal products and fresh fruits and vegetables.