Summary

During the week of June 29 to July 5, 2015 (Week 27), when a heat wave was observed across the eastern half of the country, the number of deaths recorded by participating civil registry offices (covering 70% of national mortality) increased significantly compared to the expected number of deaths. The number of deaths decreased during the week of July 6–12 (which included the second half of the heat wave), but remained higher than the expected number of deaths (Figures 1 and 2).The increase in mortality primarily affects people over 65 years of age (Figure 3) and is concentrated in nine metropolitan regions (Lorraine, Alsace, Rhône-Alpes, Franche-Comté, Île-de-France, Rhône-Alpes, Auvergne, Limousin, Poitou-Charentes, and Pays de la Loire), consistent with the area affected by the heatwave. This initial assessment of the heatwave’s impact on mortality (June 29 to July 8) requires further confirmation, given the time lags in the transmission of mortality data. 620 deaths were electronically certified during week 29 (July 13–19, 2015), a decrease compared to the two preceding weeks (Figure 4).