Outbreaks or clusters of listeriosis have historically been linked to a wide variety of commonly consumed food items, including dairy products, ready-to-eat meat and seafood products, and vegetables and fruit.
However, in South Africa, where the listeriosis outbreak closes in on 700 cases for the year, no specific food item(s) or food consumption patterns have been identified in the current outbreak.
Between 1 January and 28 December 2017, a total of 696 confirmed cases and 61 fatalities have been reported across all nine provinces in South Africa.
Gauteng Province remains the most affected, accounting for 61% (427) of the reported cases, followed by Western Cape (86, 12%) and KwaZulu-Natal (50, 7%).
The South Africa Ministry of Health is leading a multisectoral response team to investigate and respond to the outbreak, with a focus on identifying the sources.
The national authorities have made listeriosis a notifiable disease, requiring immediate reporting upon diagnosis by healthcare providers and private and public laboratories. Prior to this, limited epidemiological data are available on listeriosis in the country because it was not a notifiable medical condition prior to this outbreak.
At-risk groups for listeriosis including pregnant women, the elderly and immunocompromised people are advised to avoid high risk foods such as dairy products made from unpasteurized milk, soft cheeses, deli meat products (ready-to-eat meat cuts, pâtés, etc.), ice creams, raw vegetables, raw seafood, crustaceans, shellfish.