The warning comes as Australia steps up efforts to fight the spread of COVID-19.

Authorities are concerned that some Sydneysiders, in particular, are set to ignore government directives to "stay at home this Easter and not undertake holiday travel".

At the weekend, NSW Health Minister Brad Hazzard said their were worrying indications that many people had already ignored the do-not-travel message.

"The fact that on the North Coast, the Central Coast and the South Coast, we are seeing large numbers of people coming into those areas five days out from the Easter vacation is quite appalling," Mr Hazzard said.

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Parliamentary Secretary for the Central Coast, Adam Crouch, took the message a step further.

He advised visitors who had already arrived in the region to pack up and leave.

"If you are on the Central Coast right now but your home address is not a Central Coast suburb, please go home," he said.

The MP even urged locals to dob in tourists to Crime Stoppers.

He said locals were eyes and ears for police "so I am encouraging everyone to report any possible violations of the Public Health Order to Crime Stoppers."

Around Lake Macquarie, tourism operators would ordinarily be gearing up for a bumper long weekend.

"The Easter school holiday period is traditionally a peak tourism period for the city," a spokesperson for Lake Macquarie City Council said on Monday.

The spokesperson said it was difficult to estimate the city's income from visitors over Easter, but data on the council's website proves the COVID-19 shut-out will hurt.

The data shows domestic overnight visitors to Lake Macquarie each spend an average of $109 during their stay.

Tourism supports 2967 jobs across the city, including 1203 jobs in accommodation and food services.

Council said Lake Macquarie businesses would take a hit during the COVID-19 crisis.

"National predictions are that there will be a 30 per cent decline in jobs during the COVID-19 pandemic," the spokesperson said.

"Council understands that at this stage, those working for clubs, hotels, resorts and online travel companies are the most likely to be affected by the outbreak."

But it was not all bad news.

"Many of our hospitality businesses have been able to quickly diversify and adapt to the new COVID-19 restrictions," they said.

"Tourism and hospitality operators are working through this in interesting and diverse ways."

General examples included businesses offering virtual and online experiences such as virtual tours; online shopping and delivery of regional produce; accommodation operators providing quarantine accommodation; and restaurants offering delivery of local produce packs.

The council offered some specific examples, too.

"Matt Hall Racing and Skyline Aviation are working together to provide essential charter services, while Best Western Plus Apollo International Hotel Charlestown has approached the John Hunter Hospital to provide overflow patient accommodation."

The council has also felt the impact of the travel restrictions. Its four Lake Mac Holiday Parks - including Wangi Point Holiday Park - closed on March 26 to comply with the public health order.

The do-not-travel warning comes as the eastern side of Lake Macquarie is identified by state health authorities as a suspected hot spot for transmission of COVID-19.

Health authorities are this week increasing testing for the virus in places such as Belmont, Valentine and Windale.