The parent of two students at Southland Boys' High School and Southland Girls' High School has tested positive with coronavirus.
The students are well and without symptoms, and there was minimal risk to other students, staff or others at the school, the Southern DHB said in a letter to parents of both schools.
In case the students developed the virus in the future, they would stay at home as a precaution - the entire family had entered self-isolation.
It comes after one of eight new coronavirus cases today was announced as living in Invercargill, the Ministry of Health announced on Wednesday afternoon.
Four of the other seven patients were located in Auckland, two in Waikato and one in Christchurch - there were now 20 confirmed cases nationwide.
Contact tracing for the Invercargill patient was under way and any close contacts would be advised to self-isolate for 14 days from when they were in contact.
People were not at risk if they had been in contact with someone considered a close contact - as the close contact did not have the virus.
"Contacts of close contacts do not have to take any action such as self-isolating themselves," the DHB said.
The Otago Daily Times understood the Invercargill patient was a prominent Southlander.
Meanwhile, the staff at the office where the patient worked, Findex Invercargill, were asked to self-quarantine themselves.
A statement from Findex Invercargill detailed the individual was now in self-isolation and displaying mild symptoms. They remained in "good spirits".
"Findex is working closely with the relevant authorities and healthcare professionals and is complying with all formal advice."
The Southern District Health Board was advising people may have come into contact with the man at the following locations and times:
• The Batch Café, Invercargill, 16 March, 8.30am; 17 March, 9.30am. Casual contact – low risk;
• New World, Windsor, 12 March, 4-5pm. Casual contact – low risk;
• Waihopai Football Club – Surrey Park, Invercargill, 12 March, 6-7pm. Casual contact – low risk;
• Southland Athletic championship, Surrey Park, Invercargill, 14 March, 10-11am and 3-4pm. Casual contact – low risk.
Elsewhere, another of today's new cases arrived in the country after Monday's travel restrictions were imposed.
The woman, aged in her 40s and currently in Canterbury, arrived on Monday from London, the Ministry of Health said.
The Christchurch woman arrived in New Zealand on Monday, after the Government's tough restrictions on travellers kicked in from 1am.
Every person arriving in the country, with the exception of those from the Pacific, were ordered to self-isolate for 14 days.
The ministry publicly released the patients' flight details this afternoon.
Case number 13: Auckland, male, aged in 50s. Extensive travel through Europe - flight numbers to come.
Case number 14: Auckland, female, aged in 40s. Arrived in Auckland on Monday March 9 from Europe - flight numbers to come.
Case number 15: Auckland, male, aged in 60s. Arrived in Auckland on Friday March 13 from San Francisco on Air New Zealand flight NZ007.
Case number 16: Auckland, male, aged in 60s. Arrived on Thursday March 12 from Canada - flight numbers to come.
Case number 17: Invercargill, male, aged in 40s. Arrived on Thursday March 5 from the Gold Coast - flight numbers to come.
Case number 18: Canterbury, female, aged in 40s. Arrived on Monday March 16 from London - flight numbers to come.
Case number 19: Waikato, female, aged in 20s. Arrived on Sunday March 8 from Sydney - flight numbers to come.
Case number 20: Waikato, female, aged in 70s. Arrived on Sunday March 15 from Europe - flight numbers to come.
The Ministry of Health is yet to reveal flight numbers for all of the new cases.