How do I get listeriosis?
Physical signs, tests and treatments
Avoiding listeriosis
During the last 10 to 15 years, we have become more aware of the possibility of a woman experiencing a listeriosis infection during her pregnancy from the foods she eats. Listeriosis is relatively uncommon, but may be due to eating foods contaminated by a bacterium called 'listeria monocytogenes'. Pregnant women and their unborn babies (along with newborn babies, the elderly and people with suppressed immune systems) are particularly at risk of developing listeriosis (compared to the general healthy community who may not be affected by eating the bacteria).
The incidence of listeriosis in Australia is low with only about 34 - 71 cases being reported each year since 1990. In the year 2000, 67 cases were reported Australia wide. However, the difficulty in recognising the listeriosis illness may mean that some cases are not detected.
How do I get listeriosis?
The listeriosis microorganism is naturally widespread in nature and can be readily found in soil and vegetation. It is usually transmitted to humans through contaminated food, with recorded outbreaks being linked to dairy products (such as soft cheeses) or pre-cooked meat products (such as pate and sliced deli meat). Listeria may also be found in raw meat, raw vegetables, non-pasteurised milk and 'ready-to-eat' foods, such as diced chicken (as used in sandwich shops), oysters, smoked fish and smoked mussels. Because listeriosis can grow and multiply at temperatures as low as 0.5° Celsius (or 32.9° Fahrenheit), refrigerating these foods does not always help. However, cooking contaminated foods at high temperatures will kill the bacteria.
Another way to contract listeriosis is through the handling of miscarried products of animals, due to the listeria infection. Therefore, it is important for pregnant women working with animals not to touch these if possible (or to wear gloves if this cannot be avoided).