Omicron mutation: Higher hospitalization rate than Delta according to two new studies

Two studies conducted in Britain and published yesterday, Wednesday, as well as data also published yesterday from South Africa agree that the Omicron variant of the coronavirus seems less likely to lead to hospitalization, compared to the Delta variant.

These British preliminary investigations – one in Scotland and the other in England – were welcomed by experts, who, however, appeared cautious and stressed that the high transmission rate of the variant could nevertheless lead to more serious cases.

“What we are saying is that it is good news with ratings – with ratings because these are early observations, which are statistically significant and show us a reduced risk of hospitalization,” one of the authors of the Scottish study, Jim McMenamin, told reporters. during telephone communication.

In Scotland, investigations looked at cases recorded in November and December and grouped them into two groups: Delta on one side and Omicron on the other.

According to the study, “Omicron is associated with a two-thirds reduction in hospitalization risk for Covid-19 compared to Delta.” The study also showed that a booster dose of the vaccine provides additional protection against symptomatic infection.

This is a small study, in which no patients under the age of 60 were examined, but the authors said they adjusted these limits using statistical methods.

The second study, from the UK, found a 20% to 25% reduction in all types of hospitalizations for Omicron compared to Delta and a 40% to 45% reduction in overnight or more hospitalizations (” imports “).

Only imports were considered in the Scottish study.

“While reducing the risk of hospitalization with the Omicron variant is reassuring, the risk of infection remains extremely high,” warned Astra Ganny of Imperial College London, one of the authors of the English study. “By increasing the booster dose, vaccines continue to offer the best protection against infection and hospitalization.”

Neither of the two studies has yet been peer-reviewed, but they are being added to the growing number of data we have on Omicron. It is not clear whether the reduction in the incidence of severe cases observed with Omicron is due to the characteristics of the variant or whether this variation seems less severe because it affects populations that are more immunized as having been vaccinated or had Covid in the past. .

“This news does not detract from the extreme prevalence of this variant in the population and from the fact that even if only a small proportion of people need hospital care for Covid, the number of treatments can be very large if the rate at which continues to grow in the community, “warned Penny Ward, a professor of pharmaceutical medicine at King’s College London who did not take part in the study.

Source: AMPE