Cryptosporidium (Hansard, 20 July 1990)

§ Mr. Trippier

The report of the expert group chaired by Sir John Badenoch is being published today by HMSO. I have placed copies in the Library.

Following an outbreak of cryptosporidiosis in Swindon and that part of Oxfordshire supplied by water from Farmoor reservoir, the group was appointed in March 1989 by my right hon. Friend the Secretary of State for the Environment and my right hon. and learned Friend the Secretary of State for Health and asked to examine the implications for water supplies generally. It produced an interim report in July 1989 which formed the basis of guidance issued by Government Departments to the water industry.

Cryptosporidium has long been recognised as a parasite of animals and birds, but it was not until 1976 that it was shown to be capable of producing illness in man. Infection with cryptosporidium may cause acute diarrhoea. In 1989 there were about 9,000 reported cases of cryptosporidiosis in Britain; an increase over previous years which can be attributed in part to recent changes in laboratory sampling policies. The report concluded that water supplies can act as a source of human infection although the illness also spreads in other ways. Nationally, waterborne cases of cryptosporidiosis represent only a very small fraction of all cases of diarrhoea.

When operated optimally, the background levels of cryptosporidium oocysts in raw water sources, current water treatment processes appear able to prevent contamination of drinking water. However, they cannot be relied upon to remove all oocysts from heavily contaminated raw water.

The group highlights the importance of trying to prevent heavy contamination of raw water and of developing alternative disinfection processes to kill oocysts. It does not advocate routine monitoring of treated water for the parasite until more is known about the occurrence of cryptosporidium in the water environment 740W and techniques for its isolation and identification are improved. The group recommends that each water undertaker should develop a strategy for monitoring in certain specific situations; and that water undertakers, health authorities and local authorities should collaborate to produce detailed contingency plans for identifying, and dealing with, any outbreak of cryptosporidiosis. The report identifies a number of subjects on which further research is required.

My right hon. and right hon. and learned Friends are most grateful to Sir John Badenoch and the other members of the expert group for producing such a comprehensive and authoritative account of the present state of knowledge. The Government had accepted and endorsed their recommendations, and I have put in the Library a copy of our detailed response. Many of the recommendations involve action by other bodies, and copies of the report and the response are being sent to all water undertakers, health authorities and local authorities.

The Government already have wide-ranging polices to reduce pollution of source waters from farming activities. These include advice to farmers, generous grant aid, and regulations currently being finalised. In addition, we intend to increase the maximum fine in magistrates and sheriff courts for polluting controlled waters from the present £2,000 to £20,000 at the next legislative opportunity.

Some of the specific topics which the report identifies as needing further research have already been incorporated into a national research programme funded by this Department, the National Rivers Authority, the Foundation for Water Research and water undertakers, and supported by the Public Health Laboratory Service. This will now be extended to cover the remaining subjects.

The Government will keep the position under review, and will consider the need for further action when the findings from the research programme become available.