Abstract

Following a gradual increase in COVID-19 cases in early February, the Île-de-France region experienced rapid community spread in March, with the epidemic peaking in week 13, from March 23 to 29. The impact of the epidemic was significant in the Île-de-France region. Residents of the region accounted for approximately 40% of COVID-19 deaths recorded in France since March 1, whether in hospitals or nursing homes.
The lockdown was followed by a sharp decline in Covid-19-related healthcare utilization, first observed in outpatient settings during week 14, from March 30 to April 5, and then in hospitals starting April 7, which continued through week 24, from June 8 to 14—five weeks after the lockdown was lifted.
The epidemic remained active in the region, however, with 28 hospitalizations for COVID-19 each day (average for the week of June 8–14). The hospitalization rate remained 2.4 times higher than that observed in all other regions combined. This rate has fluctuated little over the past three weeks. When considering the earliest indicators, the situation in the Île-de-France region is similar to that of mainland France, with a standardized incidence rate from PCR tests slightly above the national average (5.7 vs. 3.8 per 100,000 inhabitants). However, there is a disparity among departments, with a test incidence rate of 7.6 in Val-d'Oise compared to 3.6 in Hauts-de-Seine. Control of the epidemic now relies primarily on cluster surveillance. This condensed issue of the PER focuses on cluster investigations in Val-d’Oise and on severe pediatric forms of the infection in Île-de-France (pediatric multisystem inflammatory syndromes).