Scientists say the bacterium, which causes an incurable bowel disease in cattle, may escape destruction by pasteurisation and could be responsible for more than 50,000 cases of Crohn's disease. John Hermon-Taylor, professor of surgery at St George's Hospital, in London, has found the bacterium, Mycobacterium paratuberculosis, is carried by two-thirds of sufferers. His team also found the microbe in 6 per cent of samples of retail pasteurised milk.
These findings have been strengthened by the work of scientists in the Northern Ireland Department of Agriculture, who found that simulated pasteurisation did not destroy MparaTB. Professor Hermon-Taylor says that increasing the temperature in pasteurisation by a few degrees would successfully eradicate the organism.
Crohn's is a painful disorder, resulting from inflammation and ulceration of the gastro-intestinal tract, most often the bowel. It is estimated that 80,000 are sufferers and 75 per cent of them need surgery. Previous British research linked the measles virus and Crohn's.
According to Action Research, which part-funded the research of Professor Hermon-Taylor, the bacterium, which infects 3 per cent of the British herd, poses no threat to the majority of the population, around 10 per cent of whom carry it with no adverse effect.
However, Anne Luther, director-general of the charity, said: "Patients with Crohn's Disease, or their close relatives who may be similarly genetically pre-disposed, may wish to switch to UHT, which is less likely to be contaminated."
Last night the Health Department refused to back the advice.
A spokesman for the National Farmers' Union said that all steps were being taken to make milk safe. "Certainly we would be concerned if it turned out to be a matter that affects people's health. What dismays us is when claims are turned into hard evidence. We are concerned that such issues can be misused."Reuse content