Know your bugs

Campylobacter

• The most common cause of foodborne illness in New Zealand.
• Risky foods include undercooked poultry, untreated water and unpasteurised milk.
• Symptoms include stomach cramps, muscle pain, headache, nausea, diarrhoea (sometimes with blood) and fever. Campylobacter can strike up to 10 days after you eat contaminated food, and effects will usually last for several miserable days.

Salmonella

• Risky foods include raw meats, poultry, unpasteurised milk and dairy products, seafood and some fresh produce. Wild birds or their droppings, and untreated drinking water are also risk factors. Salmonella is easily spread from person to person and through food.
• Symptoms include diarrhoea, headache, abdominal pain, nausea, fever and vomiting. It usually develops within two days. In recent years 11 percent of reported salmonella cases in New Zealand have been admitted to hospital.

E. coli (variant 0157:H7/VTEC)

• E. coli 0157 or VTEC produces a toxin that can destroy red blood cells and damage the kidneys.
• Risky foods include undercooked minced meat, unpasteurised milk products, unpasteurised juice and contaminated drinking water. Not washing and drying hands properly and swimming in sewage-contaminated water are also risky. If you use tank water it should be filtered and treated, or boiled for three minutes.
• Symptoms include acute gastroenteritis, watery then bloody diarrhoea, kidney failure and occasional vomiting. It usually develops within 8 days. Around 40 percent of VTEC sufferers need hospital care, and two to three percent die. Children under five, the elderly, and people with weak immune systems are at greatest risk.

Listeria

• Listeria is common but especially dangerous for the elderly and pregnant women. It can cause miscarriage or stillbirth.
• Cooking destroys listeria but, unlike other bacteria, it will grow on food in the fridge.
• Pregnant women should talk to their doctor or midwife about listeria and avoid chilled ready-to-eat foods such as soft cheeses, raw or smoked seafood, salad bar fare, cold meats, paté, pre-cooked chicken, and foods made from unpasteurised milk. (Freshly prepared salads, pasteurised dairy products and just-cooked food served steaming hot are best.)
• Symptoms include mild fever, headache, nausea, vomiting, aches and pains in the joints and muscles, or flu-like symptoms.

More information

• New Zealand Food Safety Authority www.nzfsa.org.nz