The study analyzed daily death counts in 16 European countries to assess the impact of the 2003 heat wave on mortality. Over 70,000 additional deaths occurred during the summer of 2003, with significant distortions in the age distribution of deaths but no observed harvesting effect in the months following August. The findings highlight the need for centralized daily death counts at an operational geographical scale to better detect and manage health threats, particularly in an aging population, which may be challenging to monitor at the country level due to varying mortality levels. The study also noted that global warming poses a new health threat that could be difficult to detect at the national level, emphasizing the importance of early detection through daily mortality monitoring alongside meteorological and pollution warnings.The study analyzed daily death counts in 16 European countries to assess the impact of the 2003 heat wave on mortality. Over 70,000 additional deaths occurred during the summer of 2003, with significant distortions in the age distribution of deaths but no observed harvesting effect in the months following August. The findings highlight the need for centralized daily death counts at an operational geographical scale to better detect and manage health threats, particularly in an aging population, which may be challenging to monitor at the country level due to varying mortality levels. The study also noted that global warming poses a new health threat that could be difficult to detect at the national level, emphasizing the importance of early detection through daily mortality monitoring alongside meteorological and pollution warnings.