In Japan, the first case of infection with a new type of Omicron XE strain has been detected.
The virus was found in a 30-year-old woman at a quarantine station at Narita Airport near Tokyo who had arrived from the United States. The exact strain was determined by genetic analysis.
Doctors identified three different lines resulting from mutations of the coronavirus strains: XD, XE and XF. Lines XD and XF were a combination of the “delta” variant and the “omicron” BA.1 subline, while line XE was a combination of “omicron” variants BA.1 and BA.2, in which most of the genome belongs to the latter, that is “stealth omicron”.
The WHO has declared the “omicron” XE species to be the most contagious in the history of the pandemic.