Secretary for Health, Welfare & Food Dr York Chow says there are sufficient legal grounds to name the oyster supplier involved in the recent food poisoning spate, as the move safeguards the public interest and people's health.

He said all 33 patients who came down with food poisoning symptoms recently had eaten oysters at four restaurants, and the oysters came from one supplier.

"This is very clear evidence that the oysters are the highest suspicious source of the infection. We know this supplier has also supplied oysters to many other restaurants. We feel the public have the right to know that if they have obtained oysters from this supplier, they need to be cautious," Dr Chow said.

Colon hydrotherapy

On the Consumer Council report that colon hydrotherapy lacks scientific proof to support its medical and health claims, Dr Chow said colonic irrigation is only used medically for people who need an endoscopy.

"If it is used on a therapeutic basis, there is absolutely no scientific ground. If it is going to cause danger to the public and also mislead the public, then we will have to consider whether we need to legislate," he said.

Colon hydrotherapy is not a conventional Western medical treatment and does not come under any specific Hong Kong law. So far there has been no application to list a colonic irrigation system under the Department of Health's voluntary medical device administrative control system.

Often colon hydrotherapy is promoted by its practitioners to be a safe, effective method of removing waste from the large intestine without the use of drugs. It is claimed that by introducing purified and warm regulated water into the colon, the waste is softened and loosened, resulting in evacuation through natural intestinal contraction. It is also claimed to be a method of detoxifying the body.

However, the Department of Health said there is inadequate scientific basis to support the suggestions that toxins accumulate on intestinal walls, or that toxicity results from poor elimination of waste from the colon. Further, there is inadequate scientific evidence to substantiate that colon hydrotherapy can cure specific diseases.

Hydrotherapy dangers

Relatively few injuries in relation to colon hydrotherapy have been reported in the past both abroad and in Hong Kong. In a case reported by the Hong Kong Doctors Union, a woman went through a series of colon hydrotherapy treatments due to constipation problems in July and August last year. After the eighth treatment, she suffered from severe itches. She saw a doctor and was diagnosed with venereal disease, suspected to be associated with her colon hydrotherapy.

Before patronising hydrotherapy services, people should note the possible complications of colon irrigation, including bowel perforation and infections.

Patients with gastro-intestinal illnesses or who are recovering from colonic surgery run a higher risk of bowel injury. Patients with kidney or heart failure may be more likely to experience fluid overload or electrolyte imbalances. Relying on colon hydrotherapy alone and avoiding or delaying conventional medical care may have serious health consequences.