Doherty's Sharon Lewin on pivoting from chasing COVID zero

Written by Michelle Grattan, Professorial Fellow, University of Canberra

The Doherty modelling is the government’s underpinning for a proposed easing of COVID restrictions once we reach targets of 70% and 80% of the adult population vaccinated.

But the exit path has put Scott Morrison at odds with Western Australia and Queensland, states which would inevitably have to give up their present status of having little or no COVID.

The model’s priority is pivoting from reaching zero cases, to limiting COVID by vaccination, minimising serious illness, hospitalisation, and deaths.

This week, Professor Sharon Lewin, Director of the Peter Doherty Institute for Infection and Immunity joins the podcast to explain into the much-discussed modelling and its policy implications.

In the event things open up, our “first line of defence” will be the public health capacity, says Lewin. The ability to trace, test, isolate, and quarantine limits the explosion of cases and keeps the transmission potential “less than one”.

Some critics have said the 70-80% target won’t sufficiently protect the entire population from COVID. Lewin notes that amongst the varying models there is agreement we cannot open up on vaccine uptake alone.

“You can’t just open up a 70% with nothing else in place. There is no ‘Freedom Day’. You do need these additional public health measures.”

In particular, while “tremendous advances have been made in capabilities[…] it’s not universal across the country. In particular, First Nation communities, which have been prepared and boasted an "effective community lead response” earlier in the pandemic, will require a strengthening of their public health facilities.