Several backpackers based in Bondi are among 97 new cases of COVID-19 diagnosed in NSW since Friday night.

NSW Health said there have now been 533 confirmed cases in NSW with a childcare worker at Smeaton Grange, in Sydney's south-west, also among the newly diagnosed cases.

Beachgoers descended on Bondi beach in their thousands on Friday, despite the coronavirus threat. Credit:AAP

The diagnosis of the infected backpackers comes one day after the NSW government announced a limit of 500 people for public gatherings, and was moved to close Bondi Beach after dense crowds descended on the sand on Friday and Saturday despite warnings to the contrary.

NSW Health said there were also two recent parties that some of the backpackers attended where the cases "may have acquired their infections".