Spectators will be barred from the feature race meeting at Caulfield in Melbourne but the public will be allowed into racecourses in other jurisdictions over the weekend.

Racing NSW will wait until Monday to reassess the coronavirus situation as per government guidelines with Queensland and South Australia also holding meetings on Saturday and Sunday with spectators.

The federal government has advised non-essential organised mass gatherings of more than 500 should be cancelled from Monday.

The Formula One Grand Prix in Melbourne has been closed to spectators along with various other sports including the NRL and AFL.

Racing in Hong Kong and Japan has been operating for several weeks in the absence of the public but racing in England has gone ahead as usual including this week's Cheltenham Festival.

Saturday's Caulfield meeting features the $5 million All-Star Mile and a huge crowd had been expected.

The public were also locked out of the meeting at The Valley on Friday night.

The coronavirus crisis threatens the rich Sydney autumn carnival which officially begins on Saturday at Rosehill with the Group One Coolmore Classic and the final lead-up races to the Golden Slipper a week later.

The Rosehill carnival goes for three weeks before attention switches to Randwick and The Championships.

Racing NSW and the Australian Turf Club say extra precautions will be in place on Saturday.

"Additional hygiene measures will be implemented at Rosehill for the health and wellbeing of all on course," the ATC said.

They include:

* Hand sanitiser stations in all areas with cleaning staff to continually monitor

* Additional cleaning staff to concentrate solely on the disinfection of common surfaces to continuously circulate common areas with an appropriate disinfectant chemical

The surfaces that will be done include all common door handles, handrails, common tables, lift call buttons and internal lift buttons, escalator handrails and light switches.

There will be also be no communal or buffet dining.

Racing NSW urged patrons to take precautions as per government and health professionals' guidelines.

Queensland officials will meet next week to discuss protocols and contingencies for the upcoming winter carnival.