NSW Health and the NSW Food Authority are reminding the elderly, people with weak immune systems and pregnant women to avoid risky foods, following a rise in cases of listeriosis over the past few weeks.
Eight cases of listeria infection were reported in NSW in December, compared with an average of three cases per month, of these none were fatal. Cases were aged between 64 and 90 years, and most had a condition associated with impaired immunity.
Dr Jeremy McAnulty, Director of Health Protection NSW said the increase is concerning and may indicate that people at risk for this dangerous disease are not aware that some foods are potentially harmful to them.
No common link has been identified in the recent cases.
"Listeriosis is an illness caused by eating food contaminated with bacteria called Listeria monocytogenes," Dr McAnulty said.
“Listeria infection is rare, but is particularly dangerous for pregnant women, their unborn babies and elderly people with lower immunity. It can cause miscarriages in pregnant women and death in people with weakened immune systems.”
The NSW Food Authority advises those most at risk to avoid the following ready to eat foods:
"Signs of listeriosis include flu-like symptoms such as fever, muscle aches, nausea and diarrhoea that can sometimes lead to septicemia, meningitis and in some cases, miscarriage in pregnant women," Dr McAnulty said.
Investigations into listeriosis are complex as it can be difficult to identify the source. Symptoms of illness can take up to 70 days to appear.
Healthy people usually show only mild symptoms. However, in people at risk, early symptoms of listeria infection include fever, headache, tiredness and aches and pains.
Information about listeria can be found on the NSW Health website at Listeriosis.
Information about what foods to avoid can be found at NSW Food Authority- Life events and food .