The Food Safety Information Council is using Mothers’ Day to remind mums-to-be about the risk of listeria infection during pregnancy. Between 2010 and 2014 there were 61 deaths due to listeria in Australia. While most of these cases were in adults with underlying health conditions, ten were unborn or new-born babies. Although Listeria cases are rare it can be a very serious disease and miscarriage can result if a pregnant woman is infected, even if she doesn’t show any symptoms. The time from infection to symptoms can be anywhere between 8 to 90 days.
Listeria is a bacteria found widely in the environment, so most raw foods are likely to be contaminated. Listeria is easily killed by heat, although cooked foods can easily become re-contaminated through poor food handling after cooking.This is one of the few pathogens that can grow at refrigeration temperatures, so ready to eat food should never be stored in the fridge too long. Although Listeria can grow in the fridge, it will do so very slowly so make sure your refrigerator is keeping your food at or less than 5°C. See these tips on how to avoid Listeria:
- prepare and cook your own food so you know it is fresh
- wash your hands before handling food and keep your kitchen and utensils clean
- avoid refrigerated foods that are past their ‘best before’ or ‘use by’ date
- refrigerate leftovers as soon as they stop steaming and use within 24 hours, reheat them to 75 °C
Also try to avoid foods which have a higher risk of Listeria contamination such as:
- cold meats from delicatessen counters and sandwich bars, and packaged, sliced ready-to-eat meats
- cold cooked ready- to-eat chicken (whole, portions, or diced)
- pre-prepared or pre-packaged fruit or vegetable salads, including those from buffets and salad bars
- chilled seafood such as raw oysters, sashimi and sushi, smoked ready-to-eat seafood and cooked ready-to-eat prawns
- soft, semi-soft and surface-ripened cheeses such as brie, camembert, ricotta, blue and feta
- refrigerated paté or meat spreads
- soft serve ice cream
- unpasteurised dairy products.
While it is illegal to sell unpasteurised cows’ milk in Australia, pregnant women should avoid any unpasteurised cheeses that are now being imported and, more recently, manufactured in Australia. These cheeses are labelled as unpasteurised.
For more information check this advice from Food Standards Australia New Zealand and from the NSW Food Authority on making safer food choices.