The man who has been confirmed to have New Zealand's fourth case of coronavirus attended the Tool concert at Spark Arena in Auckland on Friday night, the Health Ministry said.

Photo: Chris Schulz

Director-General of Health Dr Ashley Bloomfield said the man may have been infectious and was in the front left quadrant in the general admission standing area.

He said the risk was very low for all others who attended the concert, but people who were in that area were casual contacts - and not close contacts - so he was just advising them to be aware.

Dr Bloomfield has encouraged all people who were in the general admission standing area to be aware of the Covid-19 symptoms, which are detailed on the Ministry's website.

The man, a New Zealand citizen in his 30s, is the partner of the second case announced earlier this week, the ministry earlier said.

The Auckland couple had recently arrived back in the country from northern Italy. Contact tracing is underway and close contacts are already in self-isolation.

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Yesterday Director-General of Health Dr Ashley Bloomfield said the third confirmed case, of an Auckland man in his 40s, was one of family transmission because the man himself had not travelled to a country with coronavirus.

Officials say the man probably caught the virus from an older relative returning from Iran on 23 February.

The man's partner is now sick and being tested, and three other family members have also been ill. They have recovered and are in isolation.

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