Select Committee on Health Appendices to the Minutes of Evidence

Attachment 7



  Since it was first discovered to be a pathogen in the late 1970s, Vero cytotoxin-producing Escherichia coli (VTEC) have made their presence felt world-wide. Large outbreaks in the United States of America, central Scotland, Japan and, most recently, in Canada highlight the morbidity and mortality associated with this organism. In the United Kingdom the predominant pathogen is VTEC O157 and over 1,400 cases were confirmed by the PHLS Laboratory of Enteric Pathogens (LEP) and the Scottish E.coli O157 Reference Laboratory in 1999. The principle reservoir of infection is in cattle and the majority of human cases (>80 per cent) are sporadic (ie are not associated with outbreaks).

  The public health importance of VTEC O157 is manifested by:

    —  The substantial morbidity and mortality associated with infection. Severe complications of VTEC O157 infection include haemolytic uraemic syndrome (HUS), which mainly affects children, and thrombotic thrombocytopoenic purpura (TTP), particularly in adults. Both these complications carry significant mortality. For children developing HUS who survive a substantial proportion suffer long term kidney and/or brain damage.

    —  The fact that infection is not treatable. Therapeutic options are very limited. The mainstay of therapy includes correcting and maintaining fluid and electrolyte balance and monitoring patients for the development of HUS. A recent cohort study from the United States lends further evidence that antibiotic treatment might do more harm than good.

    —  The range of modes of transmission and low infectious dose. Although VTEC O157 infection was first recognised as food-borne, evidence accumulated from outbreak investigations and from studies of sporadic cases demonstrates several modes of transmission from the animal reservoir (food, water, environment and animal to person). Person-to-person transmission has also been demonstrated in outbreaks in households, nurseries, hospitals and nursing homes. Spread of infection by any of these means is facilitated by the fact that the infectious dose is, apparently, so small.

    —  The enormous cost in social and economic terms. The economic consequences of VTEC O157 are considerable with the cost of a single (large) outbreak having been estimated at £11.9 million over 30 years.


  Transmission to humans will continue to occur via contaminated food, water, environment and animals. The current waterborne outbreak of VTEC O157 infection in Canada 2,000 cases is a salutary reminder of the consequences of inaction.


  A variety of professionals/agencies is involved in tackling VTEC O157:

    —  at the level of individual patient care; GPs, hospital staff, health and local authority staff, the Public Health Laboratory Service;

    —  at population level; health and local authorities, the Public Health Laboratory Service, the Veterinary Laboratories Agency; and

    —  at national policy level; the Public Health Laboratory Service, the Veterinary Laboratories Agency, the Food Standards Agency, the Department of Environment, Transport and the Regions (Drinking Water Inspectorate), the Ministry of Agriculture, Fisheries and Food, the Department of Health, the Health and Safety Executive and the various territorial departments in Scotland, Wales and Northern Ireland.


  At national policy level the responsibility for VTEC O157 is split across government departments according to mode of transmission. The PHLS is the only organisation which has a complete overview of the public health implications of VTEC O157 in England, Wales and Northern Ireland. In Scotland the same applies to the Scottish Centre for Infection and Environmental Health (SCIEH). Collaboration between the PHLS and SCIEH is very strong. However, the government departments involved north and south of the Scottish border might respond differently as has been witnessed this week by the formation, in Scotland, of a Task Force to combat VTEC O157. It is understood that there are no such plans for England, Wales or Northern Ireland.


  Primary prevention of VTEC O157 is, at the moment, the only option for reducing the human toll of morbidity and mortality. This requires a wide range of activities targeted at several modes of transmission. There is an opportunity to develop a UK solution to what is undoubtedly a UK problem. The Task Force concept, involving all the key players, should be taken forward on a UK basis.


  Given the seriousness of human VTEC O157 infection, the lack of therapeutic options and the apparent lack of control measures for the animal reservoir, blocking transmission pathways is essential for reducing the morbidity and mortality from this serious disease. This requires a genuinely collaborative response right across the spectrum and including industry (farming, food, catering, water etc.) "Joined up" government needs to be just that.

  Prepared by Drs Sarah O'Brien, Goutam Adak, Robert Mitchell, Henry Smith, Frederick Bolton. Public Health Laboratory Service.

previous page contents next page

House of Commons home page Parliament home page House of Lords home page search page enquiries index

© Parliamentary copyright 2001
Prepared 28 March 2001