In week 16 (April 19–25, 2021), epidemiological indicators in the general population were once again on the decline, though at a more moderate pace than in the previous week. The reduction in hospital pressure remains very limited, particularly in critical care units. As the easing of certain restrictions approaches, epidemiological indicators remained at higher levels than those observed before the lifting of the previous lockdown, in a context where vaccination coverage among fully vaccinated individuals was increasing, reaching 9% of the population. A high level of adherence to individual preventive measures and the rapid progress of vaccination are therefore essential to allow for an imminent easing of collective measures without risking an overload of hospital capacity.

A moderate decline in the epidemic

Nationally, 202,396 new cases were confirmed, averaging approximately 29,000 cases per day. The incidence rate was declining for the second consecutive week, reaching 302 per 100,000 inhabitants in week 16 (versus 339 in week 15, a decrease of 11%). A decrease in testing rates was observed (3,036 per 100,000 inhabitants vs. 3,440, a decrease of 12%). This decrease, visible across all age groups, was most pronounced among those aged 0–14 (a decrease of 16%) and least pronounced among those aged 75 and older (a decrease of 5%). The positivity rate (9.9%) remained stable compared to Week 15.

Hospital pressure remains high

Despite the decline in incidence over the past two weeks, the reduction in hospital pressure remains very limited, particularly in critical care units. The number of reported new hospitalizations of COVID-19 patients decreased slightly (-6%). The number of reported new admissions of COVID-19 patients to critical care units in week 16 was similar to that of week 15 (2,971 vs. 2,980, or -0.3%). The number of people currently hospitalized remained high, with 30,341 people hospitalized as of April 27 (versus 31,147 on April 20, a decrease of 3%), including 5,959 patients in critical care (versus 6,000, a decrease of 1%). By comparison, one week before the lockdown was lifted on December 15, 2020, there were 25,914 patients hospitalized for COVID-19, including 3,088 in intensive care.

Beneficial effects of restriction measures confirmed

The impact of the restrictive measures was analyzed for three groups of departments in metropolitan France, defined according to the dates on which the enhanced restrictive measures were implemented (starting March 20, 2021). This analysis shows that the trend in epidemiological indicators in weeks 15 and 16 is consistent with a beneficial effect of the enhanced restriction measures, coupled with the early school break.

Nevertheless, the slowdown in viral circulation and its impact on hospital activity are occurring gradually. As the lifting of certain restrictions approaches, the incidence rate of confirmed cases in mainland France is, depending on the group, two to three times higher than that observed one week before the December 15, 2020, easing of restrictions. In this context, adherence to individual preventive measures, compliance with health protocols, and the acceleration of vaccination remain major challenges in addressing the still very high level of viral circulation.

#Flash 7: Increasingly uniform presence of variants across the country

The initial results of the Flash #7 survey from April 13, 2021, show that the circulation of the variants of concern 20I/501Y.V1 and 20H/501Y.V2 was becoming more uniform across the country. The variant of concern 20I/501Y.V1 accounted for 89.9% of interpretable sequences among the available results. The 20I/501Y.V1 variant remained particularly prevalent in Nouvelle-Aquitaine and Provence-Alpes-Côte d’Azur (>95% of interpretable sequences).

The results obtained in SI-DEP from screening PCR tests show that:

• 82.7% corresponded to a suspected 20I/501Y.V1 variant (which emerged in the United Kingdom)

• 5.0% corresponded to a suspected 20H/501Y.V2 variant (which emerged in South Africa) or 20J/501Y.V3 variant (which emerged in Brazil)

These variants were detected in all metropolitan regions. The proportion of suspected cases of the 20I/501Y.V1 variant was over 80% (among screened positive tests) in 68 metropolitan departments.

On April 29, the B.1.617 variant of the COVID-19 virus, which is widespread in India, was detected for the first time in mainland France. According to the risk analysis, the B.1.617 variant is classified as a variant of interest (VOI). See the news.

As part of the national genomic surveillance strategy led by the EMERGEN consortium, coordinated by Santé publique France and ANRS | Emerging Infectious Diseases, a system for detecting and monitoring possible cases of infection with the B.1.617 variant has been established by Santé publique France and the National Reference Center, in collaboration with clinical laboratories.

Everyone’s efforts to reduce infection rates

The decline in new cases suggests that the containment measures implemented in late March and early April are having a positive effect on the spread of the virus. Nevertheless, the level of viral circulation remains high, and the strain on hospitals is not decreasing significantly. However, high compliance with individual preventive measures will be essential to allow for an upcoming easing of collective measures without risking severe strain on hospital capacity.

Furthermore, vaccination appears to be accompanied by a relaxation of preventive measures, even though it is important to maintain them. It remains essential that anyone with symptoms suggestive of COVID-19 isolate immediately and get tested as soon as possible. The use of digital tools (TousAntiCovid) is recommended to strengthen contact tracing and rapid isolation measures.