The number of COVID-19 cases in NSW has jumped to more than 1,000 after the state recorded its first cases of the infection in children under 10.

A two-month-old boy and a seven-year-old girl, who both had contact with people with coronavirus, have tested positive, NSW Chief Health Officer Dr Kerry Chant said on Wednesday.

They are among the 1,029 confirmed coronavirus cases in NSW. Of those cases, 500 people picked up the illness while overseas.

State Premier Gladys Berejiklian says the public needs to "step up" to slow the spread of the virus, which has so far killed eight people including seven in NSW.

She also backed new public restrictions announced by the prime minister on Tuesday night to control the spread of COVID-19 following a meeting of the national cabinet of federal and state leaders.

"The decisions we take are not ones we take lightly," she told reporters in Sydney.

"This is a time that all of us have to step up. We need to make sure the community does the right thing by yourself, your family and others."

AAP

A woman in her 70s on Tuesday became the seventh person in NSW to die from the virus.

She was a passenger on the Ruby Princess cruise ship, which docked in Sydney's Circular Quay on Thursday.

"There have been 107 cases diagnosed in NSW from the Ruby Princess and 26 cases interstate," a NSW Health spokesperson said.

The woman who died was one of three initial passengers whose specimen was taken on board but tested positive after the ship docked.

Ms Berejiklian said the state was on the precipice of a more serious outbreak and had to avoid the mistakes of other countries.

She implored people to follow social distancing rules and warned authorities are "ramping up" compliance measures.

Ability to arrest

The NSW parliament on Tuesday night passed legislation to tackle the spread of coronavirus in the state.

Under the bill, state police will be able to arrest people reasonably suspected of breaching COVID-19 public health orders and return them home or to a place of detention.

The Corrective Services commissioner could grant conditional parole to certain offenders before their non-parole period if the pandemic makes it necessary.

Pubs, cinemas, gyms and churches are now closed across the nation in a bid to slow the spread of the deadly infection.

Public transport in NSW will continue to operate despite a steep decline in passenger numbers due to more people working from home.

Australians must stay at least 1.5 metres away from other people. Indoors, there must be a density of no more than one person per four square metres of floor space.

If you believe you may have contracted the virus, call your doctor, don’t visit, or contact the national Coronavirus Health Information Hotline on 1800 020 080.

If you are struggling to breathe or experiencing a medical emergency, call 000.