Australian health officials are blaming listeria-infected smoked salmon for the deaths of two people.
Both victims were aged over 70 and had "significant underlying health conditions" the country's Department of Health said.
A third person, also aged over70, had also fallen ill from eating the food.
Following the deaths, officials were urging anyone who is pregnant or has a weakened immune system to take care to avoid any food that may have the bacteria. Also, at risk are newborn babies and the elderly.
The best way to avoid becoming infected with listeria is to eat freshly cooked or freshly prepared food, health officials said.
According to the New Zealand Ministry of Health, the riskiest foods are uncooked, smoked or ready-to-eat fish or seafood; paté, hummus and tahini-based dips and spreads; cold pre-cooked chicken; processed meats; and pre-prepared, pre-packaged or stored salads and coleslaws. Raw milk and any food that contains unpasteurised milk; soft-serve ice creams; and soft, semi-soft or surface-ripened soft cheese were also listed as potential listeria-carrying foods.
Anyone who has contracted the infection may not feel any effects for a few days, or even a few weeks after eating the contaminated food.
Symptoms for listeria include mild fever, headaches, aches and pains, stomach cramps and vomiting or diarrhoea.
Anyone who thinks they may have the bacteria is urged to see a doctor.