HL Deb 22 July 1998 vol 592 cc104-6WA
The Countess of Mar

asked Her Majesty's Government:

What are the food poisoning morbidity and mortality figures resulting from infection by E.coli 0157, with source of infection, for each year from 1988. [HL2489]

0157. Lord McIntosh of Haringey

The information requested falls within the responsibility of the Chief Executive of the Office for National Statistics, who has been asked to reply.

Letter to the Countess of Mar from the Director of the Office for National Statistics, Dr. T. Holt, dated 22 July 1998.

As Director of the Office for National Statistics (ONS), I have been asked to reply to your parliamentary Question on E.coli

Morbidity

The Communicable Disease Surveillance Centre (CDSC), Scottish Centre for Infection and Environmental Health and the Medical Branch of DHSS Northern Ireland provided figures for notifications of cases from clinicians and laboratories. The number of laboratory confirmed cases of food poisoning resulting from infection by E.coli 0157 in the United Kingdom were as follows:

Year cases
1988 88
1989 207
1990 416
1991 565
1992 586
1993 506
1994 656
1995 1,046
1996 1,180
1997 1,534

Gastro-intestinal infection with pathological strains of E.coli (as with other organisms) may arise from a variety of sources. The source of infection can usually only be established through active epidemiological investigation of cases to identify potential exposures. A causal link must then be confirmed by comparing the exposure histories of those who became ill with others who did not and through bacteriological investigation of cases, foodstuffs and food preparation staff and sites.

In England and Wales, all laboratory isolates of E.coli 0157 from the Public Health Laboratory Service and the NHS are referred to CDSC for confirmation and further typing. In the five years 1992–1996 CDSC investigated 39 outbreaks of E.coli 0157 in England and Wales, with the following results:

Outbreaks 39
cold cooked meat 7
mixed foods 5
milk 3
hot beef 2
vegetables 2
unidentified food 6
total food-borne outbreaks 25
person to person outbreaks 8
contact farm animals 2
source not identified 4
Persons affected 381
of whom, deaths 14

The majority of cases in the community are isolated cases or small outbreaks affecting a single household or family. These are investigated locally by health authority and/or local authority environmental health staff, but comprehensive national data on sources of infection, follow up and fatality are not available.

Mortality

The source of infection is often unknown at the time a death is certified. In addition patients may die of a variety of complications, and the original infection may not be the certified cause of death. As a result, routine mortality statistics are not a reliable measure of deaths due to food poisoning.

E.coli infections may be coded to a variety of codes using the International Classification of Diseases Ninth Revision (ICD9) depending on body site and source of infection, if these are specified. None of the codes are specific to the 0157 strain. "E.coli food poisoning" would be coded to 005.8—other specified bacterial food poisoning. Scrutiny of the cause of death text would be necessary to identify the infecting organism and the strain (where this level of detail is supplied). ONS have cause of death text in electronic form for deaths in England and Wales since 1993, and Scotland since 1996. There is no cause of death text available in electronic form for Norther Ireland. Searching paper records for earlier years is not practicable given that the information which could only be retrieved at high cost would be of poor reliability.

England and Wales

There have been no deaths certified as due to E.coli food poisoning with or without mention of strain 0157 in the years 1993 to 1997 inclusive. There were 12 deaths certified as due to gastro-intestinal infections with E.coli (ICD-9 code 008.0). Of these, six mentioned the 0157 strain but none specified food as the source of the infection.

Year ICD-9 008.0 of which 0157
1993 0 0
1994 1 0
1995 3 0
1996 3 2
1997 5 4

Scotland and Northern Ireland

The recent outbreak of food poisoning by Eschericia coli 0157 in Scotland has been the subject of extensive investigation by a committee chaired by Professor Hugh Pennington. This enquiry established that there had been 18 deaths from the effects of E.coli 0157 infection acquired through the ingestion of contaminated meat. There were no recorded cases of food poisoning from E.coli 0157 in Northern Ireland between 1988 and 1997.