As lockdowns lift in Victoria and South Australia overnight, big problems remain in New South Wales.

A week ago, NSW had posted 110 locally acquired cases.

Yesterday, it recorded 172 new locally acquired COVID-19 cases, the highest daily number since the outbreak began in June.

So on today's Coronacast, as Sydneysiders wait to hear about the future of the lockdown, what might the NSW Government be considering?

Also on today's show:

* What is the latest on natural immunity? How long does it last?

* There was talk in Victoria with some cases testing positive on day 13 in isolation. Doesn't Delta have a quicker onset than other strains?