A crew member on a ship berthed in Taranaki is under investigation after returning a weak positive COVID-19 result.
The person tested positive, then negative during routine testing prior to a crew change.
Results of further tests are expected on Saturday and the Ministry of Health is continuing to investigate.
It said in a statement on Friday the case currently fits the pattern of an historical infection.
The ship, Boka Summit, will be moving from its berth out to sea along with other vessels in port due to the currently forecast bad weather, but is expected to reberth back in Port Taranaki after the weather has passed in the next 72 hours.
The Ministry is also continuing to investigate how the Grand Millenium worker who tested positive on Wednesday contracted the virus.
"Whole genome sequencing on the first sample has returned an inconclusive result. A repeat sequencing test is being run with results expected tomorrow afternoon - although this test may also return an inconclusive result."
No locations of interest have been identified - but Auckland public health service is continuing to work with the person to identify any possible risks.
The Ministry urges all New Zealanders to remain vigilant and protect themselves and others against COVID-19 by staying home if they feel unwell and getting tested if they have any COVID-19 symptoms.
