‘Stealth Omicron’: How dangerous is the pandemic’s new highly infectious strain of Covid-19?

Omicron BA.2, a sister variant of the fast-spreading Omicron BA.1 variant, is proving to be an even more infectious form of the new strain of the Covid-19 virus. In Hong Kong, Omicron BA.2 quickly overtook BA.1 to become the dominant strain, fuelling the largest wave of cases seen in the city so far during the pandemic. But is Omicron BA.2 more dangerous than previous strains of the coronavirus? And why is it called “stealth Omicron”? The SCMP’s Alkira Reinfrank explains.