In Week 01 (January 3–9, 2022), SARS-CoV-2 transmission increased sharply, with an incidence rate exceeding 2,000 cases per 100,000 inhabitants across all metropolitan and overseas regions. The rise in the number of hospitalizations and admissions to critical care significantly increases the strain on hospital care. However, the increase in hospital admissions is less pronounced during this wave relative to the rise in incidence. This observation is linked to the milder severity of infection with Omicron, a variant that is by far the most prevalent in the country, accounting for 89% of positive screening tests in week 01. The incidence rate was highest among those aged 20–29 (+44%) and among those aged 10–19 (+104%). As of January 11, 77.6% of the total population had received a full primary vaccination series. Among those aged 18 and older, 55.7% had received a booster dose (76.4% among those aged 65 and older). Against this backdrop of high viral circulation and rising hospitalizations, strict adherence to all preventive measures—including mask-wearing and contact reduction, as well as frequent ventilation of indoor spaces and teleworking—is more necessary than ever to help slow the spread of infections and protect the most vulnerable. Stepping up vaccination efforts, including booster shots as early as three months after the initial dose, and following all recommended measures in the event of symptoms, a positive test, or exposure to a high-risk contact are essential to limit the strain on the healthcare system.

Nearly one in five tests positive for SARS-CoV-2

Nationally, the incidence rate reached 2,811 cases per 100,000 inhabitants (vs. 1,917 in Week 52, a 47% increase), representing an average of more than 269,500 cases per day. It exceeded 2,000 cases per 100,000 inhabitants among those under 60 and remained highest among 20- to 29-year-olds (5,208, +44%). It rose most sharply among those aged 0–9 (+132%) and those aged 10–19 (+104%), as did the testing rate (up 241% and 87%, respectively), in connection with the start of the school year and the resumption of school testing. Across all age groups, the testing rate increased by 26%. The positivity rate stood at 19.8%, an increase of 2.7 percentage points.

In mainland France, the incidence rate exceeded 2,000 in all regions and was highest in Île-de-France (+30%) and Auvergne-Rhône-Alpes (+47%). It was rising across the entire country, except in Corsica, where it remained stable (+2%). In the overseas territories, the incidence rate was rising and exceeded 2,000 in all regions. It increased by 284% in French Guiana and by 194% in Guadeloupe.

New hospital and critical care admissions continue to rise

Nationally, the number of new hospitalizations (+17%) and critical care admissions (+7%) both increased this week (unconsolidated data). Among children, these increases were observed mainly in those under 1 year of age, with no signs of increased severity to date. The proportion of 0- to 17-year-olds among hospitalized COVID-19 patients remained stable (between 3% and 5%).

Furthermore, regardless of age, the proportion of symptomatic cases admitted to the hospital for COVID-19 care was lower than during previous waves. Among patients admitted for COVID-19 treatment (all types of hospitalization), 52% were infected with the Omicron variant. This proportion was lower among patients with severe cases requiring admission to critical care (including intensive care units).

As of January 11, 23,437 COVID-19 patients were hospitalized, including 3,982 in critical care. In mainland France, new hospitalizations and critical care admissions increased in most regions. In the overseas territories, the highest rates of new hospitalizations were observed in French Guiana, Mayotte, and Réunion.

Rapid Replacement of Delta by Omicron in France

In Week 01, the proportion of samples with an A0C0 screening result (absence of the E484K and L452R mutations, suggesting Omicron) continued to rise: 89% in Week 01 vs. 75% in Week 52. In mainland France, the proportion of A0C0 was over 80% in all regions, ranging from a low of 81% in Provence-Alpes-Côte d’Azur (vs. 55% in week 52) to a high of 95% in Île-de-France (vs. 90% in week 52). The proportion of A0C0 also exceeded 80% in Martinique (84%), French Guiana (88%), and Mayotte (99%). However, this was not the case in Guadeloupe and Réunion, where the proportion of A0C0 was 68% and 65%, respectively. A screening result indicating the presence of one of Omicron’s target mutations (coded D1, strong suspicion of Omicron) was identified in 88% of interpretable results (vs. 77% for S52). Conversely, the decline in the proportion of positive samples screened with the L452R mutation (carried mainly by Delta) continued: it was 11% vs. 25% in week 52. These various indicators are consistent and illustrate the continued rapid replacement of Delta by Omicron.

Furthermore, sequencing data also confirm a rapid increase in the spread of Omicron in mainland France: 41% and 65% of interpretable sequences in the Flash S51 and S52 surveys.

• For more information: see the variant risk analysis dated January 5, 2022

The B.1.640 variant is now classified as a VOI (variant of interest) based on its continued circulation in mainland France at low levels (0.1% and 0.2% in the Flash S51 and S52 surveys) and preliminary in vitro data indicating possible immune escape.

More than 4 in 10 French people have received their booster dose

As of January 11, 2022, the estimated vaccination coverage in the general population based on Vaccin Covid was 77.6% for a complete primary vaccination ^series¹ and 44.0% for the booster dose. Among those aged 18 and older, 55.7% had received a booster dose, and 66.8% of those eligible for the ^booster2 as of that date had actually received it. Among those aged 65 and older, 76.4% had received a booster dose, and 85.5% of those eligible for it as of that date had received it. In addition, 4.2% of children aged 10 to 11 had received a first dose of the vaccine (1.3% 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.

• Visit the survey page "National Census of COVID-19 Cases Among Healthcare Professionals"