New Omicron subvariants account for nearly 70 pct new cases in U.S.

A child receives a COVID-19 vaccine shot in Los Angeles, the United States, on Dec. 17, 2022. (Xinhua)

At the beginning of October, each of the two new variants, BQ.1 and BQ.1.1, accounted for about 1 percent of new infections in the United States. They replaced BA.5 to be dominant strains in the United States in mid-November.

LOS ANGELES, Dec. 20 (Xinhua) -- New Omicron subvariants BQ.1 and BQ.1.1 accounted for about 70 percent of new COVID-19 cases in the United States in the latest week, according to the latest estimates of the U.S. Centers for Disease Control and Prevention (CDC).

BQ.1.1 was estimated to make up about 38.4 percent of circulating variants in the week ending Dec. 17, and BQ.1 was estimated to make up 30.7 percent, according to CDC data.

The two variants are descendants of Omicron's BA.5 subvariant. They have been growing especially fast since October.

At the beginning of October, each of the two new variants accounted for about 1 percent of new infections in the United States. They replaced BA.5 to be dominant strains in the United States in mid-November.

BA.5 only accounted for 10 percent of new infections in the latest week.

Another Omicron subvariant XBB is also on the rise, accounting for 7.2 percent of new infections.

Researchers found that the BQ and XBB subvariants are "barely susceptible to neutralization" by the vaccines, including the new Omicron boosters, according to a study published recently in the journal Cell.

This could result in a surge of breakthrough infections and reinfections, though the vaccines have been shown to hold up against severe disease, according to the study.