COVID-19: Contact tracing underway 'out of an abundance of caution' after person travelling from New Zealand tests positive for coronavirus in South Korea

Infection in New Zealand still can't be ruled out after a traveller tested positive for coronavirus in South Korea a day after leaving NZ, Health Minister Chris Hipkins says. 

However, Hipkins says the risk to New Zealand's public health remains low and cautious steps are being taken.

The individual, a South Korean citizen, left Christchurch on July 21 and arrived in South Korea the next day after transiting in Singapore for 14 hours, testing positive for COVID-19 on arrival. The traveller arrived in New Zealand on March 18, Hipkins said.

Director-General of Health Dr Ashley Bloomfield says the Ministry of Health has not been able to talk to the person who tested positive due to South Korean privacy laws.

New Zealand officials are working with the people the person lived with in Auckland to get permission to contact the traveller directly.

Five of the traveller's household contacts are in isolation, Hipkins said.

Hipkins said the Ministry of Health is seeking information from South Korean counterparts about whether a second test has been conducted on the individual.

"The traveller had no symptoms but returned a positive test on arrival. I'm advised that the test was a rapid test, which is recognised as less reliable than the PCR tests that we do here in New Zealand," Hipkins told reporters on Tuesday.

"We have initiated a number of domestic actions out of an abundance of caution. These include prioritised contact tracing of passengers in the two rows around the traveller when they flew from Auckland to Christchurch on Flight NZ555 on July 20.

"These are individuals that would be considered close contacts should the case have been infectious whilst in New Zealand."

New Zealand hasn't had community transmission of COVID-19 in nearly three months. Hipkins said the passengers considered close-contacts have been asked to self-isolate and undergo testing.

"Contact is also being made with [other] passengers on the flight. These passengers are not considered to be close contacts - they will not be required to self-isolate or to undergo testing, they'll be provided with health information and how they can seek further advice from their GP or from Healthline should there be any reason to become concerned."

The traveller arrived in New Zealand on March 18, Hipkins said.