Cold weather rather than influenza is to blame for excess deaths and demands on health services in winter, according to a study in this week's BMJ.
Researchers in London analysed deaths in south east England from 1970 to 1999 for all causes and for influenza. The maximum and minimum temperature at Heathrow Airport each day was used to assess the relation between temperature and death. Annual deaths related to influenza were then calculated.
Of 1,265 annual excess winter deaths per million over the last 10 years, only 2.4% were due to influenza. Nationally, these excess winter deaths total 50,000 per year. The decline in influenza related deaths is probably due to immunisation and to a reduction in the number of new viral strains, say the authors.
With influenza causing such a small proportion of excess winter deaths, measures to reduce cold stress offer the greatest opportunities to reduce current levels of winter mortality. Campaigns to reduce exposure to cold outdoors provide obvious scope for future preventive action, they conclude.