A student at Southland Boys' High School may have been exposed to coronavirus after his father tested positive for the virus following a trip to the Gold Coast in Australia.

The father of students at two Invercargill high schools has tested positive for coronavirus after visiting the Gold Coast.

The infected person was the 17th confirmed case in New Zealand and one of eight new cases confirmed by the Ministry of Health on Wednesday, bringing the total number of coronavirus cases in New Zealand to 20.

Medical officer of health Dr Susan Jack, in an email to South Boys' High parents, said: "We have confirmed a parent of a student at Southland Boys' High has tested positive with coronavirus (Covid-19). Please be reassured there is minimal risk to students, staff or others at the school.

"The student is completely well and has no symptoms. He is now staying home as a precaution, in case he develops the disease in the future, and the whole family is now in self-isolation," she said.

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It is understood the man also has a daughter at Southland Girls' High School. Principal Yvonne Browning said in a Facebook post that information had been shared with school families.

The students' father, who tested positive for the virus, is aged in his 40s and arrived in Invercargill from the Gold Coast on March 10. His flight details have not yet been released.

Information released on the Ministry of Health website on Wednesday said the man had returned on March 5, but his employer has since confirmed that he arrived back in Invercargill on March 10.

The man's colleagues at Findex Invercargill have been instructed to self-isolate.

"The individual is now in self-isolation and is displaying mild symptoms, however they remain in good spirits," the company said in a statement.

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Other staff had been asked to self-isolate and the business was working to identify others who may have come into contact with the man during the virus' incubation period, a spokesperson said.

The Southern District Health Board (DHB) is also contacting people who may have come into contact with the man at the following places:

- The Batch Cafe, Invercargill, March 16 at 8.30am, March 17 at 9.30am.

- New World, Windsor, March 12, between 4pm and 5pm.

- Waihopai Football Club – Surrey Park, Invercargill, March 12 between 6pm and 7pm.

- Southland Athletic championship, Surrey Park, Invercargill. March 14, between 10am and 11am, and between 3pm and 4pm.

The risk in these instances is considered to be low. Those who believe they may have come into contact with the man are advised to monitor their health and call Healthline on 0800 358 5453 if they develop symptoms such as a cough, fever, sore throat or difficulty breathing.

Supplied Danish boxer Mikkel Kessler, right, is in isolation in Queenstown with his wife, Lea Hvidt Kessler, and their three children after a member of a film crew travelling with them tested posted for coronavirus.

The Invercargill man with coronavirus is understood to be a board member of the Southland Chamber of Commerce, which has now closed its Invercargill office, and Rugby Southland staff were sent home on Wednesday after one staff member had "possibly" been exposed to the virus.

"All staff are well and are able to work at home but are following appropriate isolation protocol," a Rugby Southland statement read.

The first case of Covid-19 in the Southern DHB area was confirmed in Queenstown on Sunday.

A Danish woman spent one night in hospital in Queenstown where she tested positive for the virus.

She is now in isolation.

Two more cases were confirmed in Dunedin on Tuesday, forcing Logan Park High School to close for at least 48 hours.

A Dunedin man in his 40s began to develop symptoms five days after returning from Europe, while his son, a student at Logan Park, also had symptoms.

Southern DHB's Gail Thomson said the board would reconsider its visiting hours at Southland Hospital this week to determine if it needed to implement restrictions.

A temporary reception desk had been set up in the hospital foyer as a precaution and anyone entering the building would be screened.

Gore Hospital has already restricted its visiting hours.