As of 20 February 2018, 915 laboratory-confirmed cases of listeriosis have been reported to the National Institute of Communicable Diseases (NICD) since 01 January 2017. So far the outbreak has already claimed 172 lives. Unfortunately, the source of the outbreak still remains unknown.

Gauteng Province accounts for 59% of reported cases, followed by Western Cape (12%) and KwaZulu-Natal (7%) provinces.

Listeria is a bacterium that is naturally found in the environment - it commonly occurs in soil, water, vegetation and in the faeces of some animals. It can contaminate a wide variety of food types, including meat and meat products, dairy products (unpasteurised and pasteurised), fresh and frozen produce (fruits, vegetables and sprouts) and ready-to-eat products. This fact, coupled with a variable incubation period that can range from 6 hours to 70 days, poses a major challenge in determining the source of the outbreak.

Various stakeholders, including numerous government departments, the healthcare sector, the veterinary public health sector, and the food industry are working around the clock to find the source of the outbreak. Specialised tests are being conducted by experts at the NICD laboratories to assist in detecting the source as soon as possible.

Protect yourself against Listeria

Members of the public are encouraged to practice the World Health Organisation’s 5 Keys to Safer Food. The people who are at high risk of developing listeriosis include:

• Pregnant women;
• Adults aged over 65 years; and
• People with weakened immune systems such as those living with HIV/AIDS, cancer, kidney or liver disease, diabetes, or persons on medication that weakens the immune system

The above group of people is advised to avoid foods that have more commonly been linked to outbreaks of listeriosis. These include processed, ready-to-eat meat products, soft cheeses, and unpasteurised milk and dairy products.  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. Such products must be avoided, or thoroughly cooked in boiling water or heated at high temperatures of 70°C or higher before eating.
World Health Organisation’s (WHO) 5 Keys to Safer Food:

• Wash hands and surfaces before, and regularly during food preparation.
• Separate raw and cooked food, and don’t mix utensils and surfaces when preparing food.
• Cook food thoroughly – all bacteria are killed above 70oC.
• Keep food at safe temperatures – either simmering hot, or in the fridge.
• Use safe water and safe ingredients to prepare food.

The NICD is optimistic that the source of this outbreak will be found, and urges members of the public not to panic unnecessarily. Members of the public are urged to be vigilant all the time by observing the above guidelines, and to assist health authorities by spreading the message as widely as possible. Those in doubt must consult their nearest healthcare practitioners.

Additional information is available at www.nicd.ac.za

Issued by Department of Health