Even though Omicron causes less severe disease in those who get it, that doesn’t necessarily make it less dangerous. There is evidence that Omicron is more contagious than the already highly transmissible Delta variant, and that the number of cases has increased rapidly in several countries.
A partial analysis by Santé publique France and several studies undergoing validation support the hypothesis of a less severe Covid-19 with the Omicron variant. The reason? This form of the virus would be found less in the lungs of infected people.
At the end of December, South Africa estimated that it had passed the peak of the Omicron wave, without the number of Covid-19-related deaths exploding. In France, Santé publique France has analyzed in detail a little more than 300 contaminations linked to this variant in its last epidemiological bulletin, published on Friday 7 January.
First lesson: 89% of cases were symptomatic. But these symptoms were mild. And out of the 225 people for whom information was available, only five were hospitalized, none of them in intensive care. It should be noted that these patients were rather young and without risk factors, which could partly explain the results.
Nevertheless, for specialists, the widespread feeling that Omicron causes less severe forms of Covid-19 seems to be confirmed. A major question is whether it is inherently less severe or whether, between vaccination and previous infections, patients are “simply” more resistant.
Fewer lung infections
The first studies on the subject, robust but in prepublication and not validated by peers, support the first hypothesis. Researchers at St. Louis University in the United States have found that the concentration of virus was about ten times lower in the lungs of rodents infected with Omicron than in those infected with other variants. The virus replicates less.
