HC Deb 17 January 2000 vol 342 cc288-9W
Mr. Hammond

To ask the Secretary of State for Health if he will state the current definition used by his Department of an epidemic. [104775]

Yvette Cooper

The epidemiologists definition of an epidemic is an increase in the frequency of occurrence of a disease in a population above its baseline level for a specified period of time. The term epidemic can be used when describing the pattern of either infectious or chronic diseases in the population.

Administrative definitions can be set for different diseases in which an arbitrary threshold is selected above which the term "epidemic" is applied. In the case of influenza, the Department introduced in 1996 an administrative definition of an "epidemic" for a rate of consultation (with a sample of general practices) of 400 per 100,000 population in a week.

Such influenza activity in England is thus monitored through the Royal College of General Practitioners (RCGP) sentinel surveillance scheme. This records the number of first visits to a general practitioner with influenza-illness. Other respiratory illnesses prevalent at this time of year are recorded separately.

This system does not and cannot measure the real incidence of influenza since it is restricted to those people who visit their general practitioner. This year a major campaign was run to encourage people to choose their own remedy, to consult a pharmacist and to use NHS Direct, as alternative sources of advice.

The severity of the disease itself can also vary from year to year. This year the elderly have been particularly affected by the complications of influenza. The level of cases of acute bronchitis, a serious complication of influenza, is the highest the RCGP surveillance system has seen for 15 years. In describing epidemics some other countries formally include measures of severity in the definition of an epidemic. For example, the United States declares an epidemic when the proportion of deaths due to pneumonia and influenza passes a certain threshold.

The Department has not introduced administrative definitions of an epidemic for diseases other than influenza.