What is driving the current wave?
It is widely thought Omicron BA.2 – a subvariant of Omicron – is behind the current surge in cases.
BA.2 is significantly more transmissible than BA.1, although it is still not clear whether it causes more severe disease.
Former World Health Organisation (WHO) epidemiologist, Professor Adrian Esterman, told ABC News: “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.
“This makes it pretty close to measles, the most contagious disease we know about.”