Up to one-third of people infected by the cryptosporidium water contamination in Galway could later develop chronic gastrointestinal problems such as irritable bowel syndrome (IBS), according to a leading expert in the field.
Professor of medicine and chief of gastroenterology at McMaster University, Ontario, Canada, Stephen Collins said his research into the role of infection in people who get food or water poisoning had shown that 7-33 per cent go on to develop IBS.
He told the Irish Society of Gastroenterology (ISG) spring meeting in Killarney of his involvement in a study into chronic bowel problems in Walkerton, Canada where 2,000 people got gastroenteritis when the water supply there was contaminated seven years ago.
"I think there is a chance that some of the people who got infected in Galway will go on to develop chronic gastrointestinal problems like IBS. I would feel from my experience in Canada and my lab research that this is a probability," he said.
Prof Collins explained that a person's chances of developing IBS would depend on the severity of their illness, ie if they were ill for more than seven days.
"Other risk factors include not vomiting during your illness, being female rather than male and previous stress. People under 65 tend to be more susceptible than older people," he said.
Once a person has been infected with a bug such as cryptosporidium, Prof Collins said there is not much that could be done to prevent IBS, for which there is no known cure.
"At the moment we are exploring the use of probiotics which seem to be the way to go.
"The infection seems to be caused by disturbance of the balance of the bacteria normally found in the gut and we are trying to use probiotics to correct this imbalance."
Prof Collins said IBS is the most common chronic gastrointestinal disease in Ireland and most countries today, yet understanding of the condition has not advanced much in the past 150 years.
The condition is characterised by patients presenting with symptoms who, when tested, have nothing apparent wrong with their bowels.
The field has been dominated by those who believe IBS is a psychosomatic condition caused by stress. However, Prof Collins does not believe it can all be in the mind or that it is just one condition.
The new president of the ISG, Prof Fergus Shanahan, said the increasing diversity and frequency of gastric infections and changing types of cancer are new challenges facing gastroenterologists today.
"There is still a very high incidence of colon cancer in Ireland but the classic cancer of the stomach, that was so common when I was a student, has practically disappeared.
"It has been replaced by a new type of cancer at the base of the oesophagus which is probably related to our changing lifestyles with people more overweight and suffering from reflux acid," he said.
Director of the Alimentary Pharmabiotic Centre and professor of medicine, University College Cork and Cork University Hospital, Prof Shanahan said that while it is always important to catch stomach cancer early, it was particularly important with the new form of the disease.
As well as new diseases, Prof Shanahan said gastroenterologists were seeing odd presentations of old diseases such as TB and coeliac disease.
