Dr Iain Gillespie from the HPA's Centre for Infections outlined these preliminary findings from the latest studies into the severe foodborne disease listeriosis across England and Wales. He was reporting to the Food Standards Agency's (FSA's) Advisory Committee on the Microbiological Safety of Food (ACMSF).
Other factors increasing older people's susceptibility to the disease include various medical conditions and increased consumption of foods such as cooked beef and ham; smoked salmon and prawns; dairy products; and mixed salads, said Gillespie.
Other vulnerable groups include unborn and newly delivered babies. Listeriosis is believed to be the most common cause of food-related deaths in the UK.
Cases of listeriosis had roughly doubled since 2001, particularly among older (60 years plus) patients. Provisionally 182 and 209 cases were reported in England and Wales in 2008 and 2009 respectively, he said.
Late last month, the FSA issued a notice that Wester Lawrenceton Farm had recalled batches of Carolla and Caerphilly cheese due to contamination with Lm.
The ACMSF subsequently agreed to recommendations contained in another paper from the FSA's Social Science Research Committee working group on Lm and domestic food storage and handling practices of the over-60s.
These recommendations called for a specially designed independent social survey on food safety and handling practices among the over-60s. They also proposed a follow-up study of specific people groups in the FSA's Food Issues Survey, exploring their beliefs and behaviours with regard to food, safety and kitchen hygiene.