There are three new cases of Covid-19 in New Zealand, all in managed isolation.

There are no new community cases, the Ministry of Health said this afternoon.

Two of the new cases arrived from the United States, and the other one from the United Kingdom. They have all been transferred to Jet Park quarantine facility in Auckland.

One previously reported case has now recovered, so the total number of active cases in New Zealand is now 56. There were 4245 tests yesterday.

Meanwhile, an investigation is ongoing into an Air New Zealand crew member who tested positive last week.

Yesterday it was announced the crew member arrived in New Zealand on December 9, on a flight from the US.

They tested positive as part of mandatory testing within 48 hours of returning from the United States.

The ministry said Air New Zealand had assured it that the person had complied with all requirements for crew flying to and from the US - and the risk to the general public was considered low.

While genome sequencing has not been finalised, early results showed no link between the crew member's test and any existing New Zealand cases. Comparison with international samples suggested that it originated in the United States, the ministry said.

All other crew members had returned negative tests and were in isolation.

The total number of confirmed cases in New Zealand is 1740.