The newer and most contagious Omicron subvariants, known as BA.4 and BA.5, now made up over 70 percent of COVID-19 infections in the United States, according to data released by the U.S. Centers for Disease Control and Prevention (CDC) this week, APA reports citing Xinhua.
The BA.5 subvariant accounted for 53.6 percent of new infections in the latest week ending July 2, while BA.4 accounted for 16.5 percent of the new infections, CDC data showed.
BA.5 has become the dominant variant in the United States.
Health experts said the newer variants are more contagious and may pose a severe threat to immune protection.
They stressed that current public health tools are still very effective against BA.4 and BA.5, including masking indoors, avoiding crowds and getting booster shots.