It is hard to capture just how much we have learned in the last 22 months about what was once known as the 2019 novel coronavirus.

Perhaps the most important lesson is a philosophical one: SARS-CoV-2 is singularly adept at finding weaknesses and exploiting them and has so far only been controlled with a multi-faceted, whole of society approach.

COVID-19 vaccines are now leading the defence and have proved an incredibly powerful tool.

The question is, will the third vaccine doses now being offered around the world be enough to turn the tide on surging infection rates and hospitalisations? Or will public health measures and new treatments be important too?