[Heat health warning systems: possibilities of improvement].

In the summer of 2003 the temperatures reached were responsible for a large number of deaths in Europe. A year after this fact, many countries had implemented some sort of plan of prevention against excessive temperatures. Plans that had already shown its ability to prevent a large proportion of avoidable mortality in other latitudes. Since then, a lot of papers have been published providing new data on health effects of a heat wave, which can help increase the efficiency of these prevention plans. Knowing the weather conditions at risk, defining "heat wave" or to take into account the time that the plan should be active from the study of the relationship between temperature and their effects on health, to identify weather patterns that modulate the relationship between temperature and mortality, locate the profile of people at risk or to develop protocols for action as accurately as possible and based on scientific knowledge are elements drawn from studies carried on in recent years that should be taken into account.