The highly transmissible Omicron subvariant XBB.1.5 now accounts for 85 percent of all COVID-19 cases reported in the United States this week, according to the
latest estimates of the U.S. Centers for Disease Control and Prevention (CDC).
The prevalence of XBB.1.5 kept increasing since late last year. It is up from 79.2 percent last week and 71.9 percent two weeks prior.
XBB.1.5 is growing in proportion in all regions nationwide, according to the CDC.
BQ.1.1 remains the second most prevalent strain at 9.4 percent.
The CDC first started tracking XBB.1.5 in November last year, when it accounted for less than 1 percent of cases nationwide. Since then, the strain is spreading quickly in the United States.
Early study suggests XBB.1.5 has a couple of concerning mutations that suggest it is even more contagious than other strains, possibly the most transmissible one so far.
While XBB.1.5 is spreading easier, scientists said it does not seem to cause more severe disease.
