The official number of French cases of the new Omicron variant is “probably hugely underestimated” due to the fact that France sequences cases on a much smaller scale, a leading epidemiologist has said.
Professor Mahmoud Zureik of the Université de Versailles-Saint-Quentin-en-Yvelines told Franceinfo that the surge in Omicron infections which is already happening across the Channel in the UK could arrive in France “in the next two to three weeks.”
In the UK, a record 88,376 new Covid cases were recorded yesterday alone, almost 10,000 more than the previous record, which had been set just a day earlier.
In France, Santé publique France reported 60,866 new cases yesterday.
Prof Zureik said that this huge increase in cases can be attributed “firstly to the heightened transmissibility of Omicron. British figures suggest that it is three to four times more transmissible than Delta, while Delta was much more transmissible than Alpha and Alpha was more transmissible than the original virus.
“There is also lots of contact between Africa and Great Britain. And above all, there is Great Britain’s capacity to effectively track the number of cases. They sequence to know if a case is Delta or Omicron. Their data is gathered at a higher rate than anywhere else in the world, covering 20% of cases.
“In France, it is more like 4% of cases. So they are sequencing four, five, six times the number of cases that France is. Which means that France’s figures are probably hugely underestimated.”
Sequencing involves analysing the genome of the virus to identify any mutations and determine the variant to which it belongs. This can take several days, and France is only sequencing around 10,000 cases per week.
In France, 310 Omicron cases have been confirmed, whereas the UK government reports that, as of yesterday (December 16), there were 11,708, and a further 37,340 suspected.
Omicron is now thought to be the dominant variant in the UK, with case numbers doubling every two to three days in some areas.
Prof Zureik added that the British wave of Omicron cases will probably arrive in France as the Alpha variant did last year. “The Alpha variant was in England in December and January, while it arrived with us in March and April.
“Now, everything is pointing to the fact that Omicron could arrive with us sooner, considering its transmissibility. Next month, or even in the next two to three weeks.”
Prof Zureik urged people to get their booster vaccine doses as soon as they can, especially if they are older or immunosuppressed.
“Studies are clear on this subject,” he said. “One vaccine with two injections is not enough. The mRNA vaccines Pfizer and Moderna protect a little against infection, but on the other hand, a booster dose protects against infection and also serious illness.”
Prof Zureik added that the French government could consider shortening the gap between second and booster doses to three months, as has already been done in the UK, but observed that this could create a huge bottleneck of people trying to book appointments.
This could prevent those who need their additional dose more urgently from accessing it.