A close contact of the covid positive security guard from Auckland's Grand Millennium MIQ has now also tested positive for the virus

There's considered little additional risk to the community as they've been self-isolating at home.

The contact, who is also a worker at the isolation facility, returned an earlier negative test before today's positive result.

The genome sequencing for the security guard shows a link with a cleaner at the facility who tested positive for Covid-19 on March 21.

The pair are genomically linked to a returnee who arrived back in New Zealand on March 13.

The investigation into how Covid-19 was transmitted to the security guard is ongoing.