Vulnerable populations: lessons learnt from the summer 2003 heat waves in Europe

What lessons can be learnt from the exceptionally long and severe heatwave experienced in Europe in 2003? First, that these heatwaves can be responsible for a dramatic excess mortality: certainly more than 50 000 excess deaths for Europe in August 2003. The consequences of the heatwave were probably underestimated in many countries, at least those based on the first estimates. This excess mortality affects vulnerable groups, particularly those who are old or ill. Identification of risk factors is a priority if the necessary prevention actions are to be implemented.