CSL Europe has confirmed that the master of a self-unloading bulker died of a Covid-19-related cardiac arrest as the ship sailed near Bergen, Norway.

The infection was discovered in a post-mortem test. Later tests also found 11 other seafarers onboard the company's 11,500-dwt Tertnes (built 1985) were infected with the virus but have only shown mild symptoms so far.

The crew will remain in isolation on the vessel at the Port of Stavanger for the next 10 days.

“CSL Europe regrets to confirm the death, from Covid-related cardiac arrest, of a captain on board the self-unloading bulk carrier Tertnes, near Bergen, Norway,” the company — a division of Canada's CSL Group — said.

“In a post-mortem test, the captain tested positive for Covid-19, although the infection was unknown prior to his death.”

The vessel was en route from Gulen in Norway to Dover in the UK when the captain suffered health problems in international waters on 24 February.

The ship, which has a crew of 18 Filipinos, diverted to the Randaberg region near Stavanger following the captain's death.

The incident is believed to be the first known case of a Covid-19-related fatality on a merchant ship.

CSL Europe said it is offering full support to the crew currently under quarantine.

“Ongoing support is being provided to the seafarers whose comfort and well-being is of paramount importance,” the company said.

“CSL is in constant contact with the quarantined crew members to ensure they are able to communicate regularly with their families and have what they need to remain healthy and in good spirits under the circumstances.”

CSL Europe said it had strict protocols in place to stop the spread of Covid-19 among its crew.

Crews are required to undergo a mandatory Covid-19 PCR test in their home country and must quarantine until a negative result is confirmed. A further 14 days quarantine is required on arrival in Europe before travelling in a sterilised vehicle to the company's ships.

CSL Europe said it believes its strict pre-boarding protocols had been followed in the case of the Tertnes. The owner is now investigating the incident with health authorities and the vessel’s ship manager, V.Ships, to determine the cause of transmission.

“CSL is deeply saddened by the loss of the captain and extends its heartfelt condolences to his family,” the company said. "The health and safety of all seafarers remain CSL’s first priority."