Why must Covid cases reach 5,000 for French lockdown to end?

In order for deconfinement to go ahead on December 15, President Macron said the number of daily Covid cases in France must be down to 5,000, and the number of Covid patients in intensive care should reach 2,500-3,000.

With the latest figures from December 9 showing 14,595 new cases in the previous 24 hours, reaching the 5,000 target by December 15 looks increasingly unlikely.

But why was this number chosen in the first place? We explain.

Read more: France ‘far from December 15 target’ of 5,000 Covid cases

Effective tracking, tracing and isolating

The point of confinement is to reduce the circulation of the virus to a level at which it can be managed, which was not the case prior to the second lockdown.

At the end of September, more than 10,000 cases were being identified every day. France’s Covid advisory body le Conseil Scientifique said in a report from September 22: “With over 10,000 cases per day, manual contact tracing becomes very difficult to do in a fast and thorough way.”

By the time confinement began on October 28, almost 40,000 cases were being detected in France on a daily basis, making it almost impossible for those laboratories to which tests were sent for analysis to keep up with demand.

On October 29, Professor Jean-François Delfraissy, president of le Conseil Scientifique, explained why scientists had come to the conclusion that daily cases must be between 5,000-8,000 to be manageable. He told news source France Inter: “Why this figure? We have given these numbers because with the number of people contaminated each day, the only strategy that we really have is to combat the virus – which is test, trace, isolate – is achievable (only by meeting these numbers).”

Success does not rely on numbers alone

However, getting cases to 5,000 a day will not guarantee that the health pandemic will stay under control - if testing, tracing and isolating measures are not properly implemented.

Dr Dominique Costagliola, research director at medical research centre INSERM, tole news source Le Figaro: “To date we have not proven that we know how to effectively track chains of transmission, or that we have a real practice of isolation for sick people and their contacts.”

She added that that the practical side of isolation had also not been addressed, such as how to get groceries, how to protect people you live with and whether to take time off work. She said: “If we don’t help people to solve these problems, isolation cannot work.”

She pointed to Asian countries, such as South Korea, as examples of highly effective national tracing and isolating strategies. Since measures were tightened in November, South Korea has reduced daily Covid cases to 230 per day.

Dr Costagliola also expressed concerns over the reliability of figures now that new testing measures have been introduced. Official daily figures are currently based on PCR tests and do not take rapid antigen tests into account. “While we do not have the [correct] number of cases, number or tests and rate of possibility, it is not possible to track the virus accurately, or to get it under control,” she said.

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