Data provides clues to omicron subvariant risks

A fast-doubling subvariant of omicron is present throughout the United States and accounts for roughly 4% of current infections, according to the Centers for Disease Control and Prevention. The BA.2 subvariant spread widely in South Africa and caused a second omicron surge in Denmark, and researchers are watching to gauge its possible trajectory in the United States. The World Health Organization called BA.2 a “variant of concern” but declined to classify it separately from omicron. Although animal studies suggested BA.2 might be more severe than the original omicron variant, data on clinical severity among residents of Denmark, South Africa and the United Kingdom did not bear this out. (NPR article, 2/21/22)