A top epidemiologist has issued a stern warning that a new variant of Covid-19 is one of most infectious diseases the world has ever seen.
Professor Adrian Esterman is among the experts raising concerns about the BA.2 sub-strain of the Omicron variant.
The former World Health Organisation scientist wrote on Twitter: “Omicron BA.2 is about 1.4 times more infectious than BA.1. The basic reproduction number (R0) for BA.1 is about 8.2, making R0 for BA.2 about 12.