NSW Health is again warning people to be careful of listeriosis, with 15 recorded cases now linked to the rockmelon outbreak.
Director Communicable Diseases NSW Health Dr Vicky Sheppeard has said that the four additional cases come from Victoria and Tasmania.
Three people have died as a consequence of contracting the disease.
"All 15 cases are elderly people, and most of them have significant underlying health conditions," Dr Sheppeard said.
"Six of these cases, including two of the people who died, are from NSW.
"We can confirm that 13 of the 15 cases consumed rockmelon before the onset of their illness. People vulnerable to listeriosis should discard any rockmelon purchased before 1 March."
Listeriosis starts with flu-like symptoms such as fever, chills, muscle aches, nausea, and sometimes diarrhoea. The symptoms can take a few days or even up to six weeks to appear after eating contaminated produce.
- NSW Health
Vulnerable people include those who are over 70, pregnant or have diabetes, cancer or suppressed immune systems.
Typically, one third of cases die.
NSW Food Authority and NSW Health are currently working together to investigate the outbreak.
Anyone at risk who has symptoms is advised to visit their doctor as soon as possible.
It is understood that there are no useful tests for infection prior to the onset of symptoms.
NSW Health reminds all people at risk of listeriosis to avoid the following foods:
- Pre-cut melons such as rockmelon or watermelon
- Pre-packed cold salads including coleslaw and fresh fruit salad
- Pre-cooked cold chicken, cold delicatessen meats, pâté
- Raw seafood, uncooked smoked seafood (e.g. smoked salmon)
- Unpasteurised milk or milk products, soft cheeses (e.g. brie, camembert, ricotta or blue-vein)
- Sprouted seeds or raw mushrooms.