According to the Centre for Enteric Diseases (CED) and Division of Public Health Surveillance and Response, Outbreak Response Unit (ORU), and National Institute for Communicable Diseases (NICD)/ National Health Laboratory Service (NHLS), as of February 27, 2018, a total of 945 cases have been reported since 1 January 2017, with 30 additional cases recorded since the last update , February 20, 2018.  To date, 743 cases were reported in 2017, and 202 cases in 2018. Females account for 55% (516/943) cases where gender is reported. Where age was reported (n=909), ages range from birth to 92 years (median 19 years) and 41% (377/902) are neonates aged ≤28 days (Figure 2). Of neonatal cases, 94% (355/377) had early-onset disease (birth to ≤6 days). Most cases have been reported from Gauteng Province (59%, 555/945) followed by Western Cape (12%, 116/945) and KwaZulu-Natal (7%, 66/945) provinces. Outcome at the end of hospitalization is known for an additional 18 cases, bringing the total with known outcome to 635/945 (67%) patients. 176 (19%) patients are known to have died.

At present, the source of the outbreak is not known. The public are advised that processed, ready-to-eat meat products, soft cheeses, and unpasteurised milk and dairy products should be avoided by persons who are at risk of listeriosis. In addition, processed, ready-to-eat meat products include viennas, polonies, russians, ham, other ‘cold’ meats, sausages, various corned meats, salami, pepperoni and similar products typically found in the processed meat sections of food retailers and butcheries should be avoided, or thoroughly cooked in boiling water or heated at high temperatures of 70°C or higher before eating.