Several patients have contracted a particular form of Covid-19: a cross between the two variants Delta and Omicron. What do we know regarding these situations reported in France since January 17, 2022?
Since the beginning of the year, a Cypriot doctor and the British health authorities have reported cases of Omicron contamination.
In France, Public Health France has taken up the subject and in turn notes the existence of contamination by this “hybrid” variant. According to the authority, the first case dates back to January 17. As of February 21, the number of “probable coinfections” was estimated at 59, details Public Health France which has set up “reinforced monitoring of Delta / Omicron co-infections in order to detect possible recombinants as early as possible”.
This situation concerns today all regions of France. Reassuringly, the circulation of the Deltacron does not seem, to date, to form a cluster.
Birth of a hybrid
These co-infections would therefore prove that we can all be contaminated by two variants simultaneously. But what happens in the event of viral recombination? When the virus replicates in our cells, a copying error occurs: the genetic materials of the two variants mix.
The first part of the copy is made from the genetic code of the first strain (Delta). Then this copying process stops to resume but from the copy of the genetic code of the second strain (Omicron). A hybrid is born.
This situation has already been described: according to Public Health France, 2.7% of recombinants linked to Sars-CoV-2 have been identified to date, out of the 1.6 million genomes sequenced since the start of the epidemic.
Deltacron under surveillance
Would Deltacron be more contagious and/or dangerous than only Delta or Omicron variants? “It is difficult to predict what the characteristics of such a recombinant will be compared to the two parental variants and to anticipate its impact on public health”, attests Public Health France.
Vigilance is still required: the World Health Organization (WHO) has classified the Deltacron variant in the list of variants placed under surveillance.
