Low immunity

Vulnerable groups

Unpleasant at the best of times, food poisoning can be more dangerous for people with low or compromised immune systems, such as:

• people with some chronic health conditions or acute illnesses
• people over 70 years of age
• children younger than 5 years whose immune systems are still developing
• pregnant women

If you are not on this list but are in doubt, please contact your doctor.

Particular care

Listeria

Listeria is destroyed by conventional cooking, but can grow in some foods in the fridge.

Infection from Listeria monocytogenes bacteria is rare and causes mild or no symptoms in healthy people, but can be very dangerous to people in vulnerable groups. In pregant women, listeria can be transmitted to an unborn baby, leading to infection in the baby, premature birth, stillbirth or miscarriage. Listeria can also make newborn babies very ill.

• you should eat only freshly cooked food and well-washed freshly prepared fruit and vegetables
• leftovers can be eaten if they are refrigerated promptly and kept no longer than a day
• it’s important not to eat food if there’s any doubt about its hygienic preparation or storage

Most chilled, ready to eat foods should be avoided altogether, unless thoroughly cooked and eaten while hot:

• soft cheese such as brie, blue, fetta, camembert and ricotta - safe if cooked hot
• takeaway cooked and chilled diced chicken - as used in chicken sandwiches
• cold meats, pate and meat spreads
• pre-prepared or packaged salads greens and salads
• raw seafood such as oysters, sashimi, smoked salmon or oysters (canned oysters are safe)
• sushi and sandwiches that contain the foods listed above in the filling
• unpasteurised dairy products such as raw goat’s milk and Roquefort cheese

Vibrio

Vibrio is a type of bacteria that can cause foodborne infections. Severe Vibrio infections are usually associated with eating raw and undercooked shellfish like oysters, pipis, mussels and cockles .

Some species of Vibrio bacteria, can cause severe illness to some vulnerable people, especially those suffering from diseases associated with the liver and stomach (eg. chronic alcoholism). In some cases, the bacteria enter the blood stream, and cause septic shock and death. Affected people may develop distinctive bulbous skin lesions.

Vibrio infections can be avoided by:

• not eating raw oysters or other raw shellfish
• handling raw shellfish carefully – cuts from the shell when open may introduce Vibrio bacteria into the wound
• cooking shellfish thoroughly
• for shellfish in the shell, either: boil until the shell opens and continue boiling for five minutes, or steam until the shells open and then continue cooking for another nine minutes
• do not eat shellfish that do not open during cooking
• boil oyster meat for at least three minutes, or fry them in oil for at least ten minutes
• ensuring cross-contamination of cooked seafood and other foods with raw seafood and juices from raw seafood does not occur

Golden rules

The golden rules of food safety are practical tips designed to help people avoid harmful food bacteria. Following the golden rules is particularly important to protect people with low or compromised immune systems.

The golden rules are:

• Keep it cold
• Keep it clean
• Keep it hot
• Check the label