Food Safety Focus (226th Issue, May 2025) – Article 4

Listeria in Frozen Confections

In March 2025, a Listeria outbreak linked to frozen confections supplied to hospitals was reported in the United Kingdom. Five patients admitted to hospitals for other health issues were treated for Listeria infections. Three of them died.

Listeria monocytogenes (LM) can contaminate a wide range of foods, but most infections are caused by eating chilled, ready-to-eat food as these foods are stored at 4°C or below for extended periods, which facilitates the multiplication of LM. While symptoms are mild for healthy people, susceptible populations, including pregnant women, infants and young children, the elderly and the immunocompromised, can suffer serious health consequences when infected.

In Hong Kong, the Food Surveillance Programme of the Centre for Food Safety collects samples of ready-to-eat food from different retail outlets, including online retailers and food factories, for testing of LM. The samples include high-risk foods such as cheeses, frozen confections, cold cuts, fruits, salads, sashimi and smoked seafood. To reduce the risks from LM, susceptible populations should avoid high-risk foods and ensure food is thoroughly cooked.