Excess winter deaths highest for five years
Excess winter mortality, England and Wales, 1995/96 to 2004/05
In the winter of 2004/05 (December to March) there were an estimated 31,600 more deaths in England and Wales compared to levels in the non-winter period (see definition below). This was an increase on the low numbers seen in the previous four years but was still less than was seen during the winter of 1999/2000, when there were 48,440 more deaths compared to levels in the non-winter period
The number of additional deaths occurring in winter varies depending on temperature and the level of disease in the population, as well as other factors.
Daily deaths (5-day moving average) for 2004/05 compared to 5-year average for 1999/00 to 2003/04, England and Wales
This higher than expected number of deaths was caused by an increase in deaths in February and March, despite lower than expected numbers in December. This is probably related to the wintry conditions and temperatures experienced in February and March and above average temperatures in December
The elderly experience the greatest increase in deaths each winter. In the winter of 2004/05 there were 24,700 more deaths among those aged 75 and over than compared to levels in the non-winter period. In contrast, there were 6,900 more deaths among those under the age of 75.
Respiratory and circulatory diseases are responsible for most of the increase seen during the winter months. Influenza is often implicated in winter mortality as it can lead to bronchitis and pneumonia, especially in the elderly, although relatively few deaths are attributed to influenza itself. However, rates of influenza activity across the winter of 2004/05 were close to or below baseline levels.
Excess winter mortality is calculated as winter deaths (deaths occurring in December to March) minus the average of non-winter deaths (April to July of the current year and August to November of the previous year).
Figures for the winter of 2004/05 are provisional, and have been rounded to the nearest 100.
Figures for the winters of 1995/96 to 2003/04 are rounded to the nearest 10.
An analysis of the factors related to excess winter mortality is in Curwen M (1997) Excess winter mortality in England and Wales with special reference to the effects of temperature and influenza. in Charlton J and Murphy M (eds) The Health of Adult Britain 1841-1994, Volume 1, TSO: London, 205-216