Key Points

• This weekly bulletin presents the latest epidemiological monitoring of the heat wave that began on July 7, 2026, covering the period from July 14, 2026, to July 20, 2026.
• On July 7, 2026, after a day at the yellow alert level, all eight departments in the Île-de-France region were raised to an orange heat wave alert. From July 11, 2026, to July 14, 2026, all departments in the Île-de-France region were under a red heat wave alert, then under an orange alert on July 15, 2026, and July 16, 2026. Since July 17, 2026, all departments have been at the green level.
• Compared to the reference period, the regional analysis of emergency care utilization shows an increase in the proportion of emergency department visits for the composite health indicator iCanicule (including hyperthermia, dehydration, and hyponatremia) among coded visits (ages 75 and older and all ages) since the start of the heatwave. There has also been an increase in the proportion of hospitalizations following visits for the iCanicule indicator among coded hospitalizations (ages 75 and older, all ages) and an increase in the proportion of hospitalizations following visits for the iCanicule indicator among visits for the composite heatwave indicator (iCanicule) (age 75 and older, all ages)
• Compared to the reference period, the regional analysis of SOS Médecins consultations indicates an overall increase in procedures for the composite health indicator iCanicule (heatstroke, dehydration) since the start of the heatwave. Among those aged 75 and older, a stabilization is observed.
• This trend falls within the expected fluctuations given the current weather conditions. The decrease in the population of the Île-de-France region due to the usual summer vacation departures explains the overall decrease in emergency room visits and SOS Médecins cases across all causes. This decrease is observable across the region as a whole.
• Nevertheless, over the previous week—from Tuesday, July 14, 2026, to Monday, July 20, 2026—there was a decrease in the absolute number of SOS Médecins calls and emergency room visits related to the heat wave, in line with the gradual transition from the red alert level to the orange level and then to the green level.