Nineteen seamen on a ship in South Port in Bluff are awaiting the results of Covid-19 tests after two of their colleagues tested positive to the virus yesterday.
It was the third vessel in New Zealand this month to have crew test positive to Covid-19.
A South Port pilot, who boarded the ship in Bluff to guide it into port, was fully vaccinated and wearing personal protective equipment (PPE).
The Ministry of Health said the Marshall Islands-flagged Mattina berthed on Sunday night and all 21 crew members were tested yesterday morning.
Tests took place on the gangway area and all appropriate protocols were followed by public health staff, including the wearing of PPE.
Rapid tests were ordered for the two symptomatic crew members.
Health officials reported their condition was improving.
The test results for the remainder of the crew were due last night.
Both crew members who tested positive joined the ship in Singapore on July 2, after providing negative pre-departure tests.
South Port said in a statement it was informed last Friday by Public Health South that two Mattina crew members were showing flu-like symptoms and as a precaution had been isolated.
Since then, South Port had worked with Public Health South and the Ministry of Health to manage the quarantining and testing of the vessel and its crew, and ensure the safety and wellbeing of its staff and the wider community.
Apart from the pilot, no one else has been on or off the ship.
Strict protocols were followed to ensure the risk to the pilot was minimised, including physical distancing requirements to ensure minimal interaction with the crew.
Bluff Community Board chairman Ray Fife said the positive cases were a concern, but the matter was in the hands of the Ministry of Health.
"The right procedures were followed, and we'll just wait and see what [the ministry is] going to do now."
Maritime Union of New Zealand national secretary Craig Harrison said union members would not be going near the ship until it was cleared by health authorities.
"We haven't had Covid come across the border at the port yet, so they're doing all the right things."
Mattina was the third vessel in New Zealand waters this month to have an outbreak of the coronavirus on board.
Earlier this month, 16 crew members on deep-sea fishing vessel Viking Bay tested positive for Covid-19, while last week fishing ship Playa Zahara had 16 positive cases among its 18 crew.