Better Assessing the Severity of Omicron and Its Impact on the Hospital System

To optimize the monitoring of hospitalizations in the context of the Omicron variant being the dominant strain, Santé publique France distinguishes between hospitalizations for COVID-19 treatment and hospitalizations for other reasons among patients who test positive for SARS-CoV-2. It is important to note that the care of these patients also impacts hospital strain caused by the epidemic, as they require specific care: isolation in a private room, protective measures for healthcare workers, a dedicated care team, and even reorganization of departments, etc.

Since the start of the pandemic, hospital indicators have included all SARS-CoV-2-positive patients, regardless of whether their hospitalization is related to COVID-19. Since January 2021, the SIVIC tool has been enhanced with a new feature that allows for distinguishing between hospitalizations for COVID-19 care and hospitalizations for other reasons among patients who test positive for SARS-CoV-2.

The proportion of patients hospitalized for COVID-19 treatment has been tracked daily by Santé publique France since January 2021. This proportion was included in the epidemiological updates for several months, then removed in week 27 of 2021 due to its stability. In fact, in 2021, the proportion of patients hospitalized for COVID-19 was 87%.

As this indicator began to change starting in late 2021, with the introduction of the Omicron variant—which quickly became the dominant strain—Santé publique France resumed publishing it in its weekly national epidemiological update as of January 13, 2022. The trend observed since S52-2021 indeed shows a decrease in the proportion of hospitalizations for COVID-19, which is explained by the lower severity and higher transmissibility of Omicron compared to the Delta variant.

Nevertheless, it remains important to continue considering all hospitalizations involving active SARS-CoV-2 infection (for COVID-19 and other reasons) to assess the overall burden on the healthcare system.

More detailed indicators available as open data

Since the interpretation of trends is impacted by the Omicron variant, Santé publique France is publishing more detailed indicators as open data starting today, Monday, January 31, 2022, to reflect these developments. These indicators are based on admission dates and are available at the regional and national levels, with data dating back to January 1, 2021.

The rates of new hospitalizations and new admissions to critical care over a 7-day rolling period, as well as the current rates of hospitalization and critical care admissions, are available in three formats:

• Hospitalizations with SARS-CoV-2 infection (as of 03/13/2020)

• Hospitalizations for COVID-19 (as of January 1, 2021)

• Hospitalizations for other reasons, with SARS-CoV-2 infection (as of January 1, 2021)

Since the start of the epidemic, Santé publique France’s goal has been to make data from surveillance systems available to everyone. The agency does this through analyses published in its weekly epidemiological report, as well as by releasing data as open data. These indicators are tailored to specific populations and regions and help inform the strategy to combat the epidemic. Expanding open-data access to all available data means enabling everyone—from citizens to decision-makers and all stakeholders—to understand and document the data, thereby helping to better address and prevent the factors affecting our health.