The Ministry of Health is investigating a suspected historical case of COVID-19 that has been detected in a crew member on the IVS Merlion which is currently docked in the Port of Tauranga.

A written statement issued by the Ministry says the crew member has returned a weak positive COVID-19 test, with a high CT value, that indicates an old infection.

It appears most likely that this crew member had COVID-19 some time ago and is no longer infectious, the statement says.

The IVS Merlion arrived into New Zealand waters on October 15 after departing Indonesia on September 24.

"This infection has not been passed on to any other crew member – they have all tested negative and have been on board the vessel for three weeks.

"As a precautionary approach the case under investigation has been isolated and has had a repeat COVID-19 test as well as a blood test. The results of these tests will confirm whether they are a historic case.

"All crew members are being treated as close contacts until the case investigation is complete.

The health staff and other port staff, who had minimal contact with the crew, have all been informed and no further action is deemed necessary, says the statement.

A Port of Tauranga spokesperson says everyone involved with the ship has been contacted and the crew has not been on shore.

"All port users follow strict safety protocols, including physical distancing and the wearing of PPE by anyone protect anyone boarding visiting vessels. All associated operational areas of the port and equipment have had an extra deep-clean as an added precaution."

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