A Sydney high school located near a coronavirus hit aged-care facility has been forced to close after a Year 11 student tested positive for the coronavirus.

Epping Boys' High School in northern Sydney was closed for the day on Friday and 1,200 students were expected to self-quarantine while state health authorities worked to establish a containment strategy.

The total number of confirmed COVID-19 infections in NSW jumped to 26 on Friday when a second aged-care nurse from the Dorothy Henderson Lodge tested positive for the virus, a day after a 95-year-resident of the facility became the state's first coronavirus-related fatality.

NSW Health Minister Brad Hazzard urged parents on Friday "not to panic but make sure your child stays at home" over the weekend.

Mr Hazzard told Nine's Today Show that the young man's condition was "not bad" but added that he was also not well.

It is currently unclear if the school will reopen on Monday, with a school spokesperson saying parents and students would be contacted if a further quarantine period was required.

Secretary of the NSW Department of Education Mark Scott said the education sector had "well-prepared continuity plans" and would be contacting parents and the broader school community with advice.

READ MORE A baby is among two new cases of coronavirus in South Australia

As the number of cases in the state skyrocket, significant concerns have been raised over the increased likelihood transmission within the community.

"Out of those 25, I think we have nine now who have actually been infected on our soil rather than coming in from overseas," he said.

"And that means that we are getting an increasing number of people who are passing that on - transmitting it - on NSW soil."

READ MORE Four Australians on board cruise ship held off California coast over coronavirus fears

A 94-year-old resident of the Dorothy Henderson Lodge aged-care facility was also confirmed to have contracted the virus on Thursday evening, bringing the total number of infections connected to the facility - which is located down the road from Epping Boys' High School - to six.

The virus was first detected within the facility when an aged-care nurse was announced to have tested positive for the virus on Wednesday.

Four residents have since tested positive; the 95-year-old woman who died, an 82-year-old man, a 70-year-old man and the above-mentioned 94-year-old.

A group of 17 young children from the Banksia Cottage childcare centre have also returned negative results to the COVID-19 screening test after they visited the Dorothy Henderson Lodge on 24 February, NSW Chief Medical Officer Dr Kerry Chant said on Friday.

But Dr Chant warned that it was likely more residents of the lodge would test positive to the virus and urged aged-care facilities to cancel visits to reduce the risk of infection.

The other newly confirmed case was a Goulburn resident who arrived in Australia from Singapore on 28 February, before travelling to Darwin three days later.

Elsewhere, Mr Hazzard said two Sydney doctors who have the virus attended the same medical workshop on 18 February, alongside 77 other medical professionals.

Dr Chant said NSW Health tracked down 76 of the conference attendees, with none of them testing positive for the virus.

The doctors, from Ryde and Liverpool hospitals, are so far the only ones who are sick from that group, and 14 days have passed, giving authorities hope that no one else has been infected.

Prime Minister Scott Morrison announced on Friday that the federal government would be providing an immediate $100 million fund to the states and territories to ensure they are able to respond to a coronavirus epidemic.

After the initial payment, Mr Morrison anticipated that the cost of the public health response could be as high as $1 billion.

"I hope it is not that much," he said. "It could be more, but we at least have to enter into these arrangements having some sense of the scale of what we're dealing with here."

With additional reporting from AAP