170 cases of the Omicron variant have been identified in France, but there are actually many

Teach – “You have to prepare, because variables are always necessary.” This is what Jean Castix said on Tuesday, December 14, when Gabriel Attal had just announced that 133 cases of the Omicron variant had been officially registered in France since the beginning of the month. In the evening, this number rose to 170, according to another dashboard Public Health France.

This may not sound like much, if not ridiculous compared to the nearly 50,000 daily cases of Covid-19 from the fifth wave, due to the delta variable. But it must be understood that these are small numbers that must be followed carefully if we are to anticipate the arrival of the Omicron variant, which is more resistant to vaccines than its predecessors. Especially since these small numbers are visibly underestimated and we are, once again, blind (or suppose one eye) in our search for variants in France.

Gabriel Attal admits there are probably more cases linked to Omicron than this official figure. But when he says that “the bulk of the cases are checked and then there’s the sequence”, the evidence isn’t there.

France is still far from the UK

For a case to be formally identified as being caused by an Omicron variant, genome sequencing for that condition must be performed. In short, we do a positive PCR test and go, in specialized laboratories, to sequence the DNA of the coronavirus to see if it contains mutations in the Omicron variant.

The problem is that we don’t concatenate all cases, far from that. During the week of November 22-28, just over 11,000 cases were sequenced. That’s just over 5% of positive cases over the same period. By way of comparison, the UK, one of the top students in the field where the Omicron variant is so widespread, during the same week had 59,126 genomes sequenced out of 295,548 positive cases, or 20% of the total.

In addition, the data that is freely accessible in France does not provide a clear picture. Admittedly, the French public health authority recently published a daily tally of the number of cases. But it’s impossible to know when the scan was done, so it’s hard to follow the progress of Omicron’s cases. The agency specifies that this monitoring is done internally with enhanced monitoring, but that these items are, for now, not available to the public.

Furthermore, while serialization is the ideal tool for making sure that variables are inventoried, there is another problem: it is very time consuming. Even in the UK, which serializes a lot and where the Omicron variant grows most exponentially, Numbers It arrives a week after detection of the condition.

To follow the evolution of the identified variants as closely as possible, it is necessary to “check” the PCR tests. To simplify it, let’s say that some variants cause a small “error” during testing, associated with certain mutations. An error of this kind makes it possible to suspect the existence of a particular breed. This is what was done for the alpha variant. Then, when Delta arrived, Public Health France changed its screening method in order to adapt the new genome for this variant.

The sort is modified, the compass is blurred

This change led at that time to discontinue daily posting of old screens. At the same time, the change in technology within the labs was arduous and clearly not fast enough to follow Delta’s progress.

Today, Public Health France has changed its examination again in order to identify the mutations more specifically allowing the presence of Omicron to be suspected. And like June with Delta, this has led to a disruption in the publication of this tracking data.

″ This results in an artificial decrease in the index related to the proportion of tests examined. When the extension of the new nomenclature is sufficient, new indications will be built on this new nomenclature”, defines Public Health France in HuffPost.

What is the speed of this increase in pregnancy? Is sufficient early warning, at a regional or departmental level, sufficient to discern large Omicron clusters very quickly? It is impossible to say at the moment, because this data is not publicly available.

In the last weekly update published by Public Health France on December 9, it was determined that 1% of the tests examined presented one of the three mutations that make it possible to suspect the presence of Omicron. But these mutations can happen by chance, so it makes sense that there is ‘background noise’. It is the upward trend in the number of these tests examined that makes it possible to better define a possible outbreak of the variant on French soil.

At the moment, these items are not accessible, except for the internal databases of Public Health France. call him HuffPostThe health agency has not yet given us details of the development of the situation. This article will be updated as necessary.

to see on HuffPostExplain the mutations of the virus in two minutes