There are to be no large changes to Victoria's lockdown restrictions, after a large jump in cases overnight and Government acceptance that the Delta outbreak can't be brought back to zero.

Apart from some small changes, such as reopening playgrounds, people in Melbourne will remain in lockdown until vaccine levels get high enough.

But that's not to say the lockdown in both Victoria and NSW has been without success. Modelling has shown many tens of thousands of cases have been prevented with the extreme social distancing.

So on today's Coronacast, what happened in Victoria and what could it mean for other states?

Also on today's show:

* An interesting study from Hong Kong on eye sight and lockdowns.

* My kid's best friends come from a family that's vehemently opposed to the vaccine. We hang out all the time. I'm not going to convince them and I don't want to stop being with them but I'm concerned there is additional risk there for us. What should I do?