Epping Boys’ High School in Sydney's north will reopen on Monday after initial fears it could remain closed for up to a fortnight when a student tested positive for COVID -19.

The 16-year-old student is the son of a Ryde Hospital healthcare worker who had contact with the 53-year-old male doctor who has the coronavirus.

A NSW Health spokeswoman on Saturday said authorities are still investigating how the boy contracted the virus, as they continue to wait for the mother's test results.

A statement from the NSW Department of Education posted on the school's Facebook page says students and staff identified as "close contacts" of the boy have been asked to self-isolate for 14 days.

Epping Boys High School will be open on Monday 9 March 2020, after consultation with NSW Health. Staff and students have been contacted and measures are in place to ensure their health and safety. For more information please see: https://t.co/ot4743iYoN — NSW DoE (@NSWEducation) March 7, 2020

A close contact is a person who has spent significant time face-to-face (15 minutes) or in an enclosed space (two hours or more).

"The school will promote the need for staff and students to remain at home if they are unwell. Those who become unwell will be sent home and asked to remain away until they are well," the statement posted on Saturday reads.

The school will be thoroughly cleaned before reopening on Monday and says it will implement "the department's infection control procedures", promoting healthy hygiene habits, upholding daily cleaning routines, and providing hand sanitiser for staff and students on school grounds.

READ MORE Coronavirus to reach 'concerning' phase in NSW over coming months

An additional six cases of COVID-19 were confirmed in NSW on Saturday, bringing the state's total to 34.

A man in his 50s, a woman in her 40s and a man in his 20s contracted the virus as close contacts of previously confirmed cases.

A man in his 40s and another female in her 40s contracted the virus through family members.

A male in his 70s exhibited symptoms a day after returning from Italy and has been diagnosed with novel coronavirus.

NSW Health is contacting passengers on flight QR908 which left Doha on 1 March.