Key Points

• In Week 19 (May 10–16, 2021), epidemiological indicators of SARS-CoV-2 circulation continued to decline in the Île-de-France region. However, they remained at levels higher than the national indicators, and the impact of this decline on hospital capacity was only moderate amid the gradual lifting of public health restrictions.

• The incidence rate for Week 19 in Île-de-France continued to decline for the sixth consecutive week, while the testing rate remained relatively stable. The positivity rate also continued to decline, both at the regional and departmental levels. However, incidence and positivity rates remained high across all age groups, particularly among those aged 15–44, who remain largely unvaccinated.

• The decline in new hospitalizations of COVID-19 patients and in the number of new admissions to critical care units, which began in Week 17, had accelerated, but pressure on the hospital system remains significant in the current context.

• Sequencing results from Île-de-France included in Flash Survey #8 of April 27, 2021, confirmed the predominance of the 20I/591Y.V1 (UK) variant in the region. The 20J/501Y.V2 (ZA) and 20H/501Y.V3 (BR) variants were detected, as well as several other variants of interest carrying the E484K mutation, whose proportions appear to be increasing rapidly in Île-de-France.

• Vaccination coverage in Île-de-France continues to increase. As of May 18, 2021, 3,423,256 residents of Île-de-France had received at least one dose of the vaccine (vaccination coverage at 27.9%) and 1,453,991 had received the full vaccination series (vaccination coverage at 11.8%).

• Although the decline in epidemiological indicators confirms the slowdown in viral circulation, transmission rates remained high in Île-de-France compared to other regions. Thus, as collective restrictions are gradually lifted, it is essential to maintain a high level of adherence to individual preventive measures, including testing and the isolation of cases and at-risk contacts. Adherence to these individual prevention measures and the rapid progress of vaccination remain essential to sustain the observed decline in transmission and preserve hospital capacity.