With parts of Australia now exceeding 90 per cent in single dose vaccinations, a former deputy chief medical officer believes COVID-19 lockdowns should now be a thing of the past.

Nick Coatsworth says the high rate of vaccination provides important relief for Australia's healthcare workers.

"If we see hospitalisation rates continue to decrease, despite NSW opening up, then it would be very difficult, in fact I don't think anyone would suggest you would need more lockdowns in that sort of situation," Professor Coatsworth told Sky News' Sunday Agenda program.

"If hospitalisation rates increase you might see more targeted restrictions coming back."

NSW, Victoria and the ACT have all emerged from lengthy lockdowns in the past couple of weeks.

He said children need to be back at school whether they are vaccinated or not, noting the deep state of anxiety among parents during lockdowns.

"It is overwhelmingly a mild disease in children, there are far more serious infectious diseases in children than COVID-19," Prof Coatsworth said.

"Ultimately, the biggest damage that we are doing at the moment is having kids not at school"

He struggled to see the justification of schools opening, then quickly closing again when there is an infection.

Education Minister Alan Tudge agreed schools need to stay open whenever possible.

"Yes, there are going to be infections in schools, but let's not close the entire school down because of one infection, let's rapidly test the close contacts of that individual child," Mr Tudge said.

Meanwhile, NSW reported 296 new coronavirus cases and four deaths on Sunday.

Victoria reported 1935 new infections and 11 deaths.

© AAP 2021