This week in Singapore, a novel coronavirus subtype dubbed XBB made an unexpectedly spectacular debut.
The number of newly reported instances of COVID more than quadrupled from Monday to Tuesday.
From 4,700 to 11,700; XBB is virtually likely to blame.
Hong Kong has recently seen the same subvariant.
XBB is a severely modified offspring of the Omicron strain of SAR-CoV-2.
It's contagiousness surpasses that of any preceding strain or subtype.