In a follow-up on the large Listeriosis outbreak in South Africa, as of 14 February 2018, 872 laboratory-confirmed listeriosis cases have been reported to National Institute for Communicable Diseases (NICD) from all provinces since 01 January 2017. In addition, NICD now reports the death toll to be at 164, 43 percent of which were babies less than a month old..
Most cases have been reported from Gauteng Province (59%, 517/872) followed by Western Cape (13%, 111/872) and KwaZulu-Natal (7%, 62/872) provinces.
The source of the outbreak remains elusive; however, as The Sunday Times reports:
The World Health Organisation (WHO) has sent a food safety expert, an epidemiologist with listeriosis experience and a communication specialist to South Africa to help identify the source of the outbreak.
A WHO spokesman was quoted in industry publications this week as saying the body was working on a “strong lead”, with laboratory results pending.
Listeria monocytogenes is bacteria that is normally found in the environment and has been found in animals, birds and vegetation. It can be found in raw foods and processed foods that get contaminated after processing. Some of the most common foods that are associated with listeriosis are raw milk, soft cheeses, vegetables, and many ready to eat meats like hot dogs, deli meats and pâtés.
Those at greatest risk of serious listeria infection include pregnant women, newborns, the elderly, and adults with weakened immune systems (AIDS patients have a significantly high chance, up to 300 times, of contracting the disease).
Most healthy persons show no symptoms of this disease. Initial symptoms of food borne listeriosis include fever, muscle aches, fatigue and sometimes gastrointestinal symptoms, such as nausea, vomiting, or diarrhea. Primarily in high risk groups but occasionally in healthy adults, the infection can spread to the blood and central nervous system where it can cause sepsis and meningitis.
Due to a naturally depressed immune system, pregnant women are about 20 times more likely than other healthy adults to contract this disease. Though many women may only experience mild flu-like symptoms,infections during pregnancy can have devastating consequences to the fetus which include stillbirth or miscarriage, premature delivery and serious infections in the newborn.
What things can you do to prevent this infection? The US CDC offers recommendations to the general public and high risk groups:
• Thoroughly cook raw food from animal sources, such as beef, pork, or poultry.
• Wash raw vegetables thoroughly before eating.
• Keep uncooked meats separate from vegetables and from cooked foods and ready-to-eat foods.
• Avoid unpasteurized (raw) milk or foods made from unpasteurized milk.
• Wash hands, knives, and cutting boards after handling uncooked foods.
• Consume perishable and ready-to-eat foods as soon as possible
Recommendations for persons at high risk, such as pregnant women and persons with weakened immune systems, in addition to the recommendations listed above:
• Do not eat hot dogs, luncheon meats, or deli meats, unless they are reheated until steaming hot.
• Avoid getting fluid from hot dog packages on other foods, utensils, and food preparation surfaces, and wash hands after handling hot dogs, luncheon meats, and deli meats.
• Do not eat soft cheeses such as feta, Brie, and Camembert, blue-veined cheeses, or Mexican-style cheeses such as queso blanco, queso fresco, and Panela, unless they have labels that clearly state they are made from pasteurized milk.
Do not eat refrigerated pâtés or meat spreads. Canned or shelf-stable pâtés and meat spreads may be eaten.
• Do not eat refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole. Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna or mackerel, is most often labeled as “nova-style,” “lox,” “kippered,” “smoked,” or “jerky.” The fish is found in the refrigerator section or sold at deli counters of grocery stores and delicatessens. Canned or shelf-stable smoked seafood may be eaten.
This very hardy bacterium can survive and even grow at refrigeration temperature. Because of this factor, Listeria presents challenges in food safety.