Key Points

In Week 08 (February 22–28, 2021), epidemiological surveillance indicators were at a very high level, reflecting intense circulation of SARS-CoV-2 in Île-de-France. They also indicated a continued increase in viral circulation throughout the region.

A rise in incidence and positivity rates persisted across all departments in the region to varying degrees and was most pronounced in Seine-Saint-Denis and Val-d’Oise. This increase also affected all age groups except the oldest (75 years and older), for whom indicators had stabilized since the previous week. The highest incidence rates were observed among those aged 15–44 for the ninth consecutive week. This is accompanied by a divergence between the infection curve among residents and that among healthcare staff in nursing homes (EHPAD) and other long-term care facilities (EHPA). Assuming that adherence to preventive measures has remained stable over time, this divergence could reflect better protection of residents following the vaccination campaign.

The continued rise in viral circulation indicators is placing increased strain on the hospital system, which has been under heavy and persistent pressure in the region for several weeks. The number of new hospitalizations for COVID-19 and admissions to intensive care units is on the rise. The upward trend in new infections is also affecting mortality; all-cause mortality indicators remain at a high level relative to the expected number of deaths in Île-de-France for the fifth consecutive week.
The increases in epidemiological surveillance indicators are occurring against a backdrop where variants, known to be more transmissible, are becoming increasingly prevalent; the 20I/591Y.V1 (UK) variant is now the dominant strain.

Analysis of the results of screening tests for variants of interest collected via SI-DEP for Île-de-France in week S08 showed a persistent increase in the proportion of suspected cases of the 20I/591Y.V1 (UK) variant. Among all screening tests performed, this variant was detected in 68.4% of cases in week S08, compared to 60.4% in week S07 and 49.0% in week S06. The increase in the proportion of the 20J/501Y.V2 (ZA) or 20H/501Y.V3 (BR) variant was more moderate (6.8% in Week 08 vs. 6.5% in Week 07). The proportion of the 20I/591Y.V1(UK) variant in positive tests is now over 60% in all departments of the region.

The COVID-19 vaccination campaign, which began in France on December 27, 2020, is expanding, and vaccination coverage continues to rise. In Île-de-France, single-dose vaccination coverage stands at 3.4% in the general population and 26.5% among the elderly (75 years and older).

The regional epidemiological situation is likely to worsen in the coming weeks. Therefore, continuing to systematically follow preventive measures remains essential. It is also crucial that anyone experiencing symptoms suggestive of COVID-19 immediately self-isolate and get tested as soon as possible. The use of digital tools (TousAntiCovid) is recommended to strengthen contact tracing and rapid isolation measures.