The researchers studied the testimonies given by some 63,000 patients, all of whom had already been vaccinated before their infection.
Article written by
Posted
Update
Reading time : 1 min.
Covid-19 symptoms last less in patients infected with the Omicron variant than in those who have contracted the Delta variant, at least when they are vaccinated, shows a study conducted in the United Kingdom and published on Friday April 8 in the journal The Lancet. This work was carried out using data collected on the British public health application ZOE.
To assess the differences in symptoms between Delta, which was largely dominant for part of 2021, and Omicron, which has supplanted it since the end of the year, the researchers studied the testimonies given by some 63,000 patients, all of whom had already been vaccinated before their infection. In those who did not have a booster, symptoms lasted an average of 8.3 days with Omicron, compared to 9.6 with Delta. The difference is even more marked in the event of a booster injection: 4.4 days of symptoms with Omicron, against 7.7 with Delta.
The study, which is to be presented soon at the European Congress of Clinical Microbiology and Infectious Diseases, also looked at the details of the symptoms. Only 17% of patients infected with Omicron lost their sense of smell, compared to 53% with Delta. Conversely, sore throats were much more frequent with Omicron.
The study also confirms the lesser danger of Omicron. It seemed already established, but it was not known if this variant was less violent or if it caused fewer hospitalizations and deaths because the population was better vaccinated. These two factors probably come into play, but this study reveals that the risk of hospitalization is reduced by a quarter with Omicron compared to Delta.