Covid-19: the Omicron variant is more resistant to the vaccine but would be less severe

The profile of the new public enemy number one is becoming clearer. After the Omicron robot portrait delivered last week by the laboratories, the real-life studies offer their first results. They come both from South Africa, the land of the variant’s emergence, and from the United Kingdom, where the Prime Minister has bet on a million doses of vaccine per day to stop the ” tsunami “ Omicron.

Tuesday, December 14, Discovery Health, South Africa’s leading private health insurance organization, has thus made public a study carried out on 210,000 positive PCR tests, collected between November 15 and December 7, among which 78,000 are attributed to the Omicron variant. They confirm the significant escape of this new variant vis-à-vis the immune system, while attributing to it a lesser severity – except, perhaps, for children.

The first big question was Omicron’s ability to bypass the immune defenses built by the vaccine. The study delivers a mixed result. The double dose of Pfizer loses a large part of its capacity to protect against infection with SARS-CoV-2: the efficacy drops from 80% against contamination by the Delta variant to 33% against contamination by Omicron. “A significant fall”, insists the organization in a press release. This results in a very high risk of infection in people who have already been vaccinated or infected – and an intense circulation of the virus, even in widely vaccinated countries.

On the other hand, the two-dose regimen of the American laboratory retains an effectiveness of 70% against hospitalizations linked to Omicron. Here again, the drop is significant, compared to the 93% recorded against Delta. But, for Professor Glenda Gray of the South African Medical Research Council, “The protection remains good (…), [c’est] a very encouraging result ”. The study also specifies that “Protection against hospitalization remains important at all ages”, with 60% efficiency in the 70-79 age group.

An increased risk of hospitalization in those under 18

Epidemiologists will have another, potentially valuable data: that of severity. This is apparently good news. According to the study, the risk of hospitalization with Omicron is reduced by 29%, compared to the figures recorded during the first wave. In addition, fewer hospitalized people are admitted to intensive care. Discovery Health President Dr Ryan Noach urges caution, however. According to him, this lesser severity could result “Antibodies accumulated in the South African population by previous waves”.

You have 62.41% of this article to read. The rest is for subscribers only.