How the omicron subvariant BA.5 became a master of disguise – and what it means for the current COVID-19 surge

The new BA.5 subvariant has caused a sharp rise in cases and hospitalizations throughout much of the United States. Irfan Khan/Los Angeles Times via Getty Images

The omicron subvariant known as BA.5 was first detected in South Africa in February 2022 and spread rapidly throughout the world. As of the second week of July 2022, BA.5 constituted nearly 80% of COVID-19 variants in the United States.

Soon after researchers in South Africa reported the original version of the omicron variant (B.1.1.529) on Nov. 24, 2021, many scientists – including me – speculated that if omicron’s numerous mutations made it either more transmissible or better at immune evasion than the preceding delta variant, omicron could become the dominant variant around the world.