Brazilian authorities said Friday they had quarantined a Bahamas-flagged cruise ship with 600 people aboard after a passenger was diagnosed with a suspected case of the new coronavirus.

The man, a 78-year-old Canadian resident, was taken ill as passengers were disembarking in the northeastern resort city of Recife Thursday, developing a fever, cough and breathing trouble, the Pernambuco state health department said in a statement.

Emergency took him to a local health center, then ordered a quarantine for the others on the ship—317 passengers and 291 crew—even though some were already ashore.

"As soon as identified a suspected case of COVID-19, the National Health Vigilance Plan was put in action to immediately suspend other passengers from disembarking and ask tourism agencies to return those who had already left the ship," the statement said.

"All will be kept in their cabins... and a monitoring team has been mobilized to assist in the investigation and the that will be implemented."

TV images showed the ship, a towering white cruise liner, docked in Recife. It had previously downed anchor in Salvador, on Brazil's northeast coast.

The quay where it is docked has been isolated, and the ship will be required to keep its trash on board, the health department said.

Brazil has reported 77 coronavirus cases, with no deaths so far.

But concern is starting to spread, with even President Jair Bolsonaro—who had called coronavirus fears "overblown"—undergoing a test, which he announced had come back negative.