Experts, governments around the world, WHO… Everyone assures us: the Omicron variant is spreading at an unprecedented rate, like no other before it. As a result, since its discovery less than a month ago in South Africa, the number of cases has exploded.
Except in France, where there are officially less than 400 cases of Omicron. At the same time, just Tuesday evening, some 73,000 new contaminations coronavirus were identified in 24 hours. Would France be spared by who knows what divine grace? Has the government found the miracle cure for the pandemic? Or are the numbers underestimated?
In comparison with other countries, are the French figures realistic?
Countries around the world are bearing the brunt of the expansion of the Omicron variant. In mid-December, the Health Security Agency in the United Kingdom assured that the new variant was progressing at the rate of 200,000 infected people per day and could reach between 300,000 and 400,000 cases per day before the end of the year. In Spain, Omicron accounted for 47.2% of new cases diagnosed between December 6 and December 12. On Wednesday, the Danish government estimated that Omicron was now in the majority, less than a month after its first detection in the country. The day before, the US government announced the same sentence with an Omicron that would represent
73% of new contaminations.
Suddenly, France and its 347 official cases on December 17 are a bit surprising. The day before, the 16th, Olivier Véran nevertheless put forward a good reason, that of an effective “isolation, tracing, contact tracing, sequencing, screening” strategy which made it possible to slow the progression of the variant “successfully”. .
Olivier Véran “We are successfully braking the Omicron variant” pic.twitter.com/eksrIVWEz8
– BFMTV (@BFMTV) December 16, 2021
Why are the numbers fuzzy?
Quite simply because not everyone gives exactly the same numbers. On Tuesday, government spokesman Gabriel Attal announced that approximately20% of positive cases for Covid-19 in France now fell under the highly contagious Omicron. He said that at the end of last week, it represented only 10% of contaminations. For its part, Public Health France indicates that among the positive cases sequenced during the week of December 6,
97% are linked to the Delta variant and 2.1% Omicron.
Finally, the Covid Tracker site ensures that “it is suspected that Omicron represents up to 10.3% of positive cases in France “. The tool which makes it possible to follow the evolution of the epidemic specifies that this percentage is based only on “the proportion of tests screened not having the L452R mutation”. What slightly tangle the brushes.
How do you know that contamination is linked to Omicron?
The detection is done in two stages. Screening, then sequencing. When an individual’s test is positive, they are screened. That is to say that scientists will identify one or two mutations that compose it. We know, for example, that the L452R mutation is present on the Delta variant, but not in Omicron.
If it comes out, it’s negative at Omicron. But if it is missing, it means that Delta is left out; the scientists then proceed to a more in-depth study of the test: it is the sequencing, that is to say the complete study of the viral genome. The screening therefore gives a trend, but not an exact result, and the sequencing takes a little more time.
Are we doing enough sequencing?
On December 14, Gabriel Attal said on Franceinfo that “most of the positive cases that are detected in France” were screened, then sequenced. “We do more than 10,000 sequencing per week”, said the spokesperson of the government, specifying that this made it possible “to identify rather widely the cases (Omicron) on our soil”. Except maybe the reality is a little different. Identification of Omicron involves screening PCR assays only. However, all people who discover that they are positive for the coronavirus via an antigen test do not necessarily do a PCR test afterwards (even if it is normally mandatory).
Furthermore, figures published by Public Health France show clearly that the tests are not at all screened mainly on the whole of the territory. Between December 12 and 18, only 19% were screened on average, the rates varying according to the departments, from 0% in Calvados to 60% in Sarthe.