The Omicron variant of Covid, which first reached France in December 2021, is continuing to mutate, with cases of subvariants BA.4 and BA.5 having now been detected in the country.
The BA.2 subvariant already makes up more than 96% of all French Covid cases, and now BA.4 and BA.5 (also known as XE and XD) are being closely observed by health authorities.
Santé publique France has confirmed that one case of the former and two of the latter have been confirmed in the country.
BA.4 and BA.5 differ slightly from the original Omicron variant, and have been produced by ‘errors’ occurring when the virus penetrates human cells, causing its genetic make-up to mutate.
The European Centre for Disease Prevention and Control has urged countries to be especially vigilant towards these subvariants, not “because of their epidemiological or clinical characteristics, but because of their genetic profile,” Santé publique France stated.
This is because both subvariants contain the L452R mutation, which can also be observed in the Delta variant.
“This mutation has been associated with an increased transmissibility,” Santé publique France said.
“We are therefore asking what the impact of this mutation will be.
“We have less than 300 sequences [reflecting the genetic make-up of the subvariants] at our disposal in our international database,” but several organisations in France are now working to find out more about them.
These subvariants are being monitored closely so that health authorities have more information on the evolution of the Covid virus, but they are not considered to be variants ‘of concern’.
So far, the three BA.4 and BA.5 cases have “not revealed anything worrying in terms of symptoms or clinical presentation.”
Some 104,007 Covid cases were recorded in France yesterday (April 21), marking a reduction of 24% on the same time last week.