Listeria has been found in Food Science Annex, while documents suggest the presence of bacteria for over a year.
On 12 March, UCD Food Science students were informed that the Food Science Annex would be temporarily closed due to a listeria contamination. The bacteria was detected during routine testing, with a “substantial sanitation programme” underway after measures to eliminate it were unsuccessful. However, records show that listeria, which made national headlines in July 2025 after an outbreak resulted in the death of 1 person, was present in the Annex for at least 18 months.
Listeria is a deadly pathogen with mortality rates as high as 40%. It is primarily transmitted through the consumption of contaminated food items, with unpasteurised dairy products and ready-to-eat meals common carriers. While anybody can become ill from contracting the bacteria, pregnant women, babies, and those with weak immune systems are most at risk. The presence of listeria in food development kitchens has previously closed facilities permanently.
Chemical testing records show that food developed in the Food Science ‘Product Development’ module tested positive for listeria in November 2024. Of the 9 groups tested, 6 contained the bacteria. Records also show that listeria was present in the food of 7 of the 9 groups tested in the same module in 2025. Despite this, some students were first told of the issue in early February.
One student, speaking anonymously to the University Observer, expressed their frustration with the timing of the announcement. Their year-long research project has been fundamentally changed, being forced to discard data and a product they have worked on since September. They are concerned that the School of Food Science has not communicated when listeria was first identified in the Annex, noting that they ate lunch in the contaminated kitchen.
The student feels the timing of UCD’s announcement of the Annex’s closure was due to questions they raised about contamination, though the university has not commented on this. Having spoken with a lab technician who could not provide an answer on the presence of listeria, the student was told by a senior professor that they could not use the Food Science Annex, but that a kitchen in the O’Brien Centre for Science was available. However, after further questions to their supervisor, and research project module coordinator regarding safety, this offer was rescinded and the kitchen’s closure was announced.
Signs of listeriosis include flu-like symptoms, meningitis, and septicaemia. While there is no evidence to suggest anyone has been infected or suffered illness due to its presence in the Food Science Annex, any student who is experiencing symptoms or is concerned about their health is advised to contact the UCD Student Health Service or their GP and follow HSE guidance.