An escalation in the spread of the epidemic

Week 1 (January 4–10, 2021) was marked by an increase in epidemiological indicators, which could foreshadow an even greater rise in the number of cases in the coming days.

With an average of 18,000 confirmed cases per day during Week 1 (totaling 126,022 cases), the incidence rate increased by 30% compared to the previous week. The increase was observed across all age groups and was most pronounced among those under 20.

After a sharp decline observed last week, testing rates are on the rise (+9% between Week 53 and Week 1 and -39% between Week 52 and Week 53). Thus, 1,953,125 people were tested, representing a rate of 2,910 per 100,000 inhabitants. Among symptomatic individuals, this increase was 34% compared to Week 53, accounting for 22% of those tested, while it remained stable among asymptomatic individuals (+1%). The positivity rate (6.5%) continues to rise compared to the previous week (+1.1 percentage points).

In hospitals, indicators are on the rise. After a decrease in week 52, followed by stabilization in week 53, the number of reported new hospitalizations for COVID-19 increased between weeks 53 and 01: 8,872 new hospitalizations were reported in week 01 compared to 7,460 in week 53, a 19%increase. An increase in the number of new intensive care admissions between weeks 53/2020 and 01/2021 is observed (+21%), but the increases by reporting date may be due to the backfilling of data that could not be recorded during the end-of-year period. Thus, by admission date, the increase is smaller, but the data have not yet been consolidated [+6% and +5% respectively—see page 33 of the epidemiological report].

The emergence of new variants: enhanced surveillance and flash investigation

As soon as the VOC 202012/01 variant detected in the United Kingdom and the 501Y.V2 variant detected in South Africa emerged, enhanced surveillance was implemented. The aim is to assess and monitor the spread of these variants across the country. As soon as a case is detected, all healthcare stakeholders are mobilized to assist those affected in tracing their potential contacts and ensuring strict isolation to break transmission chains.

At the same time, to establish an initial map of the extent of the spread of the VOC 202012/01 variant in France, a Flash survey was proposed to all public and private clinical laboratories (LBM) by Santé publique France and the CNR Virus des infections respiratoires (Lyon Associated Laboratory, Prof. Bruno LINA); it was conducted on January 7 and 8, 2021, in collaboration with the network of hospital virologists coordinated by the ANRS Emerging Infectious Diseases.

This survey is based on a two-step approach applied to samples for RT-PCR: screening using ThermoFisher® RT-PCR, which generates so-called “discordant” RT-PCR results and raises suspicion of a possible VOC 202012/01 variant; and, in a second step to confirm these suspicions, sequencing of these samples with discordant results to confirm or rule out the presence of the variant.

To date, 89 laboratories spread across the 13 regions of metropolitan France have participated in the study, representing 25% of the RT-PCR tests that returned positive results nationwide over the two days of the study. The analysis thus covered 97,664 RT-PCR samples, including 7,465 samples with a positive RT-PCR result, of which 281 were discordant.

The initial results published today provide preliminary estimates of the variant’s circulation:

• The proportion of discordant RT-PCR results, relative to the total number of positive RT-PCR tests, is 3.8%. Furthermore, based on CNR surveillance data, it is estimated that 38% of discordant results are variants confirmed by sequencing. Based on these data, it is thus possible to estimate—pending confirmation by sequencing—that this variant accounts for 1 to 2% of COVID-19 cases currently diagnosed in France.

• The proportion of discordant RT-PCR results also varies from one region to another, suggesting a heterogeneous presence of the VOC 202012/01 variant across the country. However, these geographical comparisons should be interpreted with caution due to low participation in the survey in certain regions.

This survey will be repeated at regular intervals. The consolidated results of this first edition will be released once all sequencing data and results are available.

Prevention measures and vaccination: two essential tools for tackling the epidemic

Against a backdrop of rising infection rates, barrier measures and contact tracing remain the primary individual and collective means of curbing the spread of the SARS-CoV-2 virus and reducing its impact on the healthcare system and mortality rates. Adherence to these measures is all the more essential in light of the identification of emerging variants, which pose a risk of increased transmissibility.

At the same time, the vaccination campaign has intensified since January 4, 2021. It initially targets residents of long-term care facilities and healthcare professionals, and is being extended to people over 75 as well as those with underlying conditions that make them vulnerable to severe forms of the disease. The rollout of vaccines across regions is underway to increase vaccination coverage among the population. Pending indicators based on the Vaccin Covid information system and data provided by the Regional Health Agencies (ARS), 247,166 people had been vaccinated against COVID-19 in France as of January 13, 2021.

Accelerating vaccination is essential to reduce the number of severe cases of COVID-19 as quickly as possible and enable a return to a life closer to normal.