NEW YORK/TOKYO -- In just few months span, the newest coronavirus subvariants are well on the way to supplanting previously dominant strains in the U.S. and other countries.
After initial reports of the omicron variant appeared in South Africa nearly a year ago, it has become prevalent across the globe and it has given rise to several subvariants. The most common strain, BA.5, is now giving way to new sublineages led by BA.4.6.
