Cryptosporidium (Hansard, 28 July 1989)

§ Mr. Howard

Sir John Badenoch, chairman of the group of experts, wrote to my right hon. and learned Friend the Secretary of State for Health and my right hon. Friend the Secretary of State for the Environment on 25 July 1989 to present the group's interim report. Copies of the letter have been placed in the Library. The establishment of the group was announced on 2 March 1989, at column286, and an interim report was requested by the end of July.

The interim report says that the organism cryptosporidium has a worldwide distribution. Although it has long been recognised as a parasite of animals, it was not until 1976—a little over a decade ago—that it was shown to be capable of producing illness in man. Infected animals including man excrete the organism in their faeces in the form of minute oocysts which may cause infection if they are ingested.

In man, cryptosporidiosis is usually characterised by a self-limiting illness with diarrhoea, abdominal cramps, vomiting and sometimes fever that resolves in one to three weeks. It can affect persons of any age but is most common in children between the ages of one and five years. In patients with AIDS, and others whose resistance to infection is impaired, it is much more serious and may lead to severe and lasting disability.

Because of the organism's widespread distribution, the group indicates that it must be assumed that, from time to time, oocysts will be present in all surface waters including springs and shallow wells. Current methods of water 1189W treatment and disinfection properly carried out cannot eliminate entirely the risk of cryptosporidium passing into the water supply.

However, though the group recognises the potential that exists for giving rise to a very large number of cases through public water supplies it points out that an individual is much more likely to contract the infection if he comes into direct contact with the faeces of an infected person or animal.

The letter points to the need for high standards of maintenance and repair of water distribution systems, for extra monitoring at water treatment works in certain circumstances and for some modification of operating procedures should the organism be detected in significant numbers. Close collaboration between water undertakers, local authorities and health authorities is advocated. A co-ordinated programme of research is proposed for gathering information on the occurrence of cryptosporidium and the capacity of water treatment works to remove it.

I am advised that the expert group has spent considerable time examining the more general public health aspects of cryptosporidiosis and will make a fuller report in due course. In its interim report it identifies those most as risk from contracting the disease and puts forward simple precautions for prevention.

My right hon. Friends welcome the interim report and are grateful to Sir John and his colleagues for the considerable effort they have made so far in undertaking this study. The Departments will draw the attention of water undertakers, local authorities, health authorities and other organisations to the interim conclusions and recommendations. Ways of undertaking the proposed research are already under consideration.