The Omicron Covid variant has been found to multiply about 70 times quicker than the original and Delta versions of coronavirus in tissue samples taken from the bronchus, the main tubes from the windpipe to the lungs, in laboratory experiments that could help explain its rapid transmission.
The study, by a team from the University of Hong Kong, also found that the new variant grew 10 times slower in lung tissue, which the authors said could be an indicator of lower disease severity.
The initial data, published online and not yet peer-reviewed, came from experiments using lung tissue samples taken from patients during surgery. By 24 hours, the Omicron variant had replicated about 70 times more than Delta and the original variant. Although the bronchus is not the upper respiratory system, scientists said this could lead to people shedding more virus and passing on infections more easily.