Listeria (Hansard, 16 February 1989)

§ Mr. Robin Cook
To ask the Secretary of State for Health whether his Department has received any data on whether the use of microwave ovens for reheating cook-chill meals will eliminate listeria.

§ Mr. Kenneth Clarke
The research projects listed by my hon. Friend the Parliamentary Secretary to the Ministry of Agriculture, Fisheries and Food in his reply to the hon. Member for South Shields (Dr. Clark) on 9 February 1989 at columns780–81 include one on microwave ovens. The information obtained from these studies will be made available to my Department.

§ Mr. Robin Cook
To ask the Secretary of State for Health what is the safe threshold of listeria in food consumed by a pregnant women.

§ Mr. Kenneth Clarke
The 1988 World Health Organisation working group indicated that virtually nothing is known about the infectious dose of listeria monocytogenes in man, although it may be related to host susceptibility. Advice was given to pregnant women and other vulnerable groups last week about certain soft cheeses and other foods which may present a risk.

§ Mr. Robin Cook
To ask the Secretary of State for Health what is the relationship between the increase in listeriosis and the consumption of cheeses over the most recent convenient period.

§ Mr. Kenneth Clarke
Although it is most likely that listeriosis is a foodborne disease, the cause of most cases is as yet unknown. However, high numbers of listeria have been found in several varieties of soft cheeses, and a number of cases of listeriosis—both in this country and abroad—have been associated with eating heavily contaminated soft cheese. For this reason, the Government's chief medical officer has advised pregnant women and people recovering from serious illness to avoid eating soft cheese.

§ Mr. Robin Cook
To ask the Secretary of State for Health whether he has received any report from the public health laboratory service on the incidence of listeria in pre-cooked chickens.

§ Mr. Kenneth Clarke
At my Department's request, the public health laboratory service recently carried out a survey of the prevalence of listeria monocytogenes contamination in certain cooked chilled foods. This showed that 12 per cent. of the pre-cooked ready-to-eat poultry purchased from retail outlets contained listeria. monocytogenes. Adequate reheating will destroy the organism.
343W
This was the basis of the advice given to pregnant women and other vulnerable groups on Friday 10 February that they should thoroughly reheat such foods. The recent survey was fully taken into account when that advice was issued. The latest survey does not indicate a degree of risk which would justify dietary advice to healthy adults who would be very unlikely to suffer adverse effects from the levels of contamination detected.
I will be laying regulations under the Food Act to ensure better temperature controls in retail refrigerated units. We have been engaged in talks with the Ministry of Agriculture, manufacturers, retailers and caterers aimed at developing a code of practice and improving procedures in the handling of retail cooked poultry and chilled meals.

§ Mr. Kennedy
To ask the Secretary of State for Health how many cases have been identified in the past 10 years of meningitis caused as a result of consuming United Kingdom-produced listeria-infected cheese.

§ Mr. Kenneth Clarke
There has been one case of listeria meningitis in the past 10 years which was microbiologically associated with a United Kingdom-produced cheese. The cause of most cases of listeriosis remains unknown, although it is most likely that it is foodborne.

§ Mr. Churchill
To ask the Secretary of State for Health how many cases of listeria in the United Kingdom have been identified in the past 10 years as having been caused by cheese made from unpasteurised milk products produced(a) within the United Kingdom, (b) in France and (c) in any other country; and if he will publish the scientific evidence available to him on the risk presented by such cheese.

Mr. Kenneth Clark
Two reported cases of listeriosis have been directly attributed to the consumption of cheese made from unpasteurised milk, one produced in the United Kingdom and one in France.
There has been a variety of published evidence indicating the risk associated with both unpasteurised and pasteurised soft cheeses. In particular, the "Report of the WHO Informal Working Group on Foodborne Listeriosis", Geneva 15–19 February 1988 and "Occurrence in the UK of Listeria specis in Raw Chicken and Soft Cheeses" published in the International Journal of Food Microbiology 1988 Vol. 6. However, as he indicated in his public statement on 10 February 1989, the Government's chief medical officer has recently been taking further expert advice on the risks.