In Week 10 (March 7–13), the incidence rate, which remained at a very high level, began to rise again (+25%). The effective reproduction number, which is above 1, confirms the acceleration of SARS-CoV-2 transmission across the country. The number of new hospital admissions has, however, stabilized. In the overseas territories, the incidence rate was particularly high in Martinique (>3,100 per 100,000 inhabitants). Admissions to intensive care and deaths, meanwhile, continued to decline. The BA.2 sublineage of the Omicron variant has been the dominant strain in mainland France since Week 09 (57%). As of March 15, vaccination coverage was generally stable compared to the previous week: 83.0% of those aged 65 and older and 74.4% of those aged 80 and older had received a booster shot. Given the increased circulation of SARS-CoV-2 and influenza viruses, maintaining preventive measures remains recommended, particularly to protect the most vulnerable (wearing a mask in poorly ventilated or crowded spaces, handwashing, and ventilating enclosed spaces). Vaccination efforts for people aged 80 and older must now include the second booster dose for eligible individuals. Compliance with other measures—particularly in the event of symptoms, a positive test result, or exposure to a high-risk contact—as well as participation in contact tracing remain essential.

Incidence rate rising after six weeks of decline

Nationally, the incidence rate rose in week 10, following six consecutive weeks of decline, reaching 686 cases per 100,000 inhabitants (+25%), or more than 65,000 new cases on average per day. This increase was observed across all age groups. The incidence rate was above 800 among 6- to 10-year-olds (+39%), 11- to 14-year-olds (+41%), and 30- to 39-year-olds (+22%). The testing rate also increased (+11%) after several weeks of decline. While stable among those aged 90 and older, it rose the most among 3- to 5-year-olds (+28%) and 6- to 10-year-olds (+39%). After a week of stabilization at a high level, the positivity rate also began to rise again (23.4%, +2.7 percentage points).

In mainland France, the incidence rate increased in all regions, ranging from +4% in Occitanie to +40% in Hauts-de-France. It was highest in Brittany (1,002, +27%) and in the Grand Est (998, +31%). The testing rate was also on the rise across the entire country and was highest in the Grand Est (3,657, +15%), in Provence-Alpes-Côte d’Azur (3,428, +5%), and in Corsica (3,326, +5%). In the overseas territories, the incidence rate increased across all regions except Mayotte and stood at 3,182 per 100,000 in Martinique (+29%), exceeding the level reached at the start of the year (3,149 in week 03). It was above 1,000 in Guadeloupe (+55%) and Réunion (+8%).

New hospital admissions have stabilized, while admissions to intensive care continue to decline

Nationally, the number of new hospital admissions has stabilized (-5%), while the decline in new critical care admissions has continued (-17%). The number of deaths in hospitals and long-term care facilities continued to decline, as did all-cause mortality, which has been falling since Week 06, though with an excess just below the threshold of statistical significance among those aged 65–84 in Week 09.

In mainland France, rates of new hospitalizations stabilized or were slightly down, except in Hauts-de-France (+17%). In the overseas territories, rates of new hospitalizations remained highest in Réunion, although they were slightly down.

The dominant BA.2 sublineage now accounts for 57% of Omicron sequences

Sequencing data confirm the dominance of Omicron in France and the near-disappearance of Delta circulation. Omicron accounted for more than 99.9% of interpretable sequences in the Flash S09 survey (02/28).
In addition to the three Omicron sublineages BA.1, BA.2, and BA.3, other sublineages have been identified within BA.1 (36 as of 03/16). These BA.1 sublineages result from a highly detailed genetic classification aimed at tracking Omicron’s evolution, and there is currently no indication that they possess characteristics (in terms of transmissibility, immune evasion, and severity) different from those of the original BA.1 sublineage. Consistent with trends from previous weeks, the BA.2 sublineage is now the dominant strain in France, accounting for 57% of the 2,002 Omicron sequences in the Flash S09 survey. The rise of BA.2 at the expense of BA.1 is observed throughout mainland France, but at varying levels across regions.

Since February 18, 2022, a Delta/Omicron recombinant has been subject to enhanced monitoring by the laboratories of the EMERGEN consortium, Santé publique France, and the CNR Virus des infections respiratoires. It has been assigned the lineage XD and is therefore now the official name of this recombinant. The majority of the XD variant’s genome corresponds to the Delta variant (AY.4 sublineage), but a large portion of the S gene (encoding the spike protein) corresponds to the Omicron variant (BA.1 sublineage). As of March 14, 41 sequences of the XD variant had been detected in France, including 21 during Flash surveys. These sequences correspond to cases from several regions dating back to early January 2022, suggesting low-level circulation for several weeks. To date, very little data is available on the characteristics of the XD variant, but investigations are ongoing. More information is available in the variant risk analysis dated 02/23/2022

83% of those aged 65 and older have received a booster dose

As of March 15, 2022, the estimated vaccination coverage in the general population was 79.5% for a complete primary vaccination series and 58.4% for the booster dose. Among those aged 18 and older, 73.0% had received a booster dose, and 82.6% of those eligible for the booster as of that date had actually received it. Among those aged 65 and older, 83.0% had received a booster dose, and 91.0% of those eligible for the booster as of that date had received it. Additionally, 9.3% of children aged 10 to 11 had received a first dose of the vaccine (3.1% for those aged 5 to 9).

Furthermore, Santé publique France has published an update on the surveillance of COVID-19 cases among healthcare workers in healthcare facilities and a summary of contact tracing activities.