The fast-spreading BA.4 and BA.5 sub-lineages of Omicron are estimated to make up a combined 70.1% of the coronavirus variants in the United States as of July 2, the U.S. Centers for Disease Control and Prevention said on Tuesday.
BA.4 and BA.5 made up 52% of U.S. variants for the week of June 25. They were added to the World Health Organization’s monitoring list in March and designated as variants of concern by the European Centre for Disease Prevention and Control.
Last week, the U.S. Food and Drug Administration recommended that COVID-19 vaccine makers change the design of their booster shots to include components tailored to combat BA.4 and BA.5.
BA.4 made up 16.5% of the variants in circulation, the latest data showed, while BA.5 accounted for 53.6%.