Seven previously announced COVID-19 cases in Port Stephens were linked to a Sydney visitor, and three Hunter businesses - the Wallsend Diggers, Hotel Jesmond and the Lambton Park Hotel - were temporarily closed for deep cleaning after a Sydney construction worker attended the venues while infected.

Toronto Court House also underwent deep cleaning following another Sydney visitor testing positive for COVID-19 after attending the site early last week.

The cases and closures have prompted Wallsend MP Sonia Hornery to call for the NSW Premier to "ban" - rather than advise - non-essential travel from Sydneysiders to Newcastle before cases "spiral out of control".

"All of the recent cases in the Hunter are from the Sydney clusters," Ms Hornery said. "We need decisive action from the Premier on people travelling here from Sydney."

Hunter New England Health public health physician, Dr David Durrheim, said there was "clearly a risk" and echoed Premier Gladys Berejiklian's advice that there should be no non-essential travel in NSW.

"It should not be happening - particularly from Sydney into regional NSW," Dr Durrheim said. "Non-essential travel should be off the table at the moment.

"There is clearly a risk and we don't want the risk introduced here. We don't want people travelling from the Hunter down to Sydney unless it's absolutely essential, and if they must, we ask them to take every precaution necessary - which may include a face mask as well."

Hunter New England Health did not announce any new local cases on Tuesday, but Dr Durrheim hoped people viewed the close calls as a warning to go back to meticulously following social distancing and hand hygiene measures.

"I also think people need to be their own COVID safety inspectors and make sure the gym, or the pub or club they are attending is doing the right thing," he said.

Hunter New England Health could not tell the Newcastle Herald how long the Sydney construction worker had been in the region.

But any areas or venues where there was a high risk of exposure had been announced.

"We go through and if there are limited exposures - less than five minutes, which is sometimes the case if someone is picking up a coffee order or filling up with fuel and paying by tapping their card, that doesn't count as a close contact," he said.

Ms Hornery said some people who had attended the Lambton Park Hotel, Hotel Jesmond and Wallsend Diggers had not been contacted by contact tracers.

She said her office had been contacted by about 50 people who were still waiting to hear from health officials. She said some were unaware they were required to isolate for 14 days if they were at the venues at the specified times.

"My office has had calls and messages from people who have not been contacted by Health to advise them what they need to do," she said.

"Health are basically saying that if you signed in at 6.55pm [rather than from 7pm] to the Jesmond Hotel on Wednesday night, you won't be contacted to advise that you should be tested and isolate."

Dr Durrheim said they had contacted more than 200 people following the confirmation the Sydney case had visited Newcastle.

"As part of the contact tracing process, those who registered at the venues within the relevant times are contacted and given advice that they should self-isolate for 14 days and be tested for COVID-19 as soon as possible," he said.

Hunter New England urges anyone who attended any of the following three venues to strictly isolate at home for 14 days from those dates and be tested for COVID-19.

- Hotel Jesmond on July 29 between 7pm and 9pm

- Wallsend Diggers on July 29 and July 30 between 9pm and 11pm

- Lambton Park Hotel on July 30 between 8pm until 9pm.

"We encourage members of the community to follow the NSW Health and HNE Health Facebook pages to ensure they have the latest information and advice."

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