A sailor from the USS Theodore Roosevelt has died of coronavirus just days after the aircraft carrier's captain was fired for criticising the US Navy for not doing enough to contain an outbreak among his crew.

Key points: The sailor was transferred to an intensive care unit after being found unresponsive on April 9

The sailor was transferred to an intensive care unit after being found unresponsive on April 9 Doctors declared the sailor dead on April 13

Doctors declared the sailor dead on April 13 The ship's captain had previously called for more to be done to protect sailors and was later dismissed for circulating his concerns too widely

The sailor, whose name has not been made public, is the first active-duty member of the US military to die of COVID-19.

After testing positive on March 30, he was taken off the ship and put in an isolation house on Naval Base Guam, along with four other sailors.

"Like other sailors in isolation, he received medical checks twice daily from Navy medical teams," a Navy statement said.

"At approximately 8:30am on April 9, the sailor was found unresponsive during a daily medical check.

"While Naval Base Guam emergency responders were notified, CPR was administered by fellow sailors and [an] onsite medical team in the house.

"The sailor was transferred to US Naval Hospital Guam where the sailor was moved to the intensive care unit.

"The sailor was declared deceased April 13."

Captain raises alarm

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USS Theodore Roosevelt arrived in Guam on March 27 for a scheduled port visit for resupply and crew rest.

At the start of the month, nearly 100 sailors had tested positive for the virus.

In a four-page letter to Navy leaders the ship's then-captain Brett Crozier said the spread of the disease on the ship was ongoing and accelerating.

He advocated for removing all but 10 per cent of the crew, saying it was a "necessary risk" in order to stop the spread of the virus.

"We are not at war. Sailors do not need to die," he said.

"If we do not act now, we are failing to properly take care of our most trusted asset — our sailors."

Nearly 3,000 sailors of the ship's crew of almost 5,000 were then brought ashore to Guam.

But shortly afterwards the US Navy fired Captain Crozier, saying his letter had created panic.

Captain Brett Crozier's letter called on the Navy to do more to safeguard his crew from coronavirus. ( Reuters: US Navy )

Navy Secretary Thomas Modly said the captain copied too many people on the memo, which was leaked to a California newspaper and quickly spread to many news outlets.

But in videos posted online, sailors applauded Captain Crozier and hailed him as a hero who defended his crew at the cost of his career.

"And that's how you send out one of the greatest captains you ever had," exclaimed one sailor in a video post, amid thunderous applause and cheering for Captain Crozier as he left the carrier and its crew members in Guam.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 34 seconds 34 s Footage shared online shows sailors applauding Captain Crozier as he leaves the ship.

Less than a day after the dismissal, more than 120,000 people signed a petition calling for him to be reinstated.

Mr Modly was later condemned over a speech he gave to the crew in which he criticised Captain Crozier, saying he was either "too naive or too stupid" to be in charge of an aircraft carrier.

He issued a public apology over the comments, but Democrats in Congress called for his resignation and Mr Modly stepped down from his role.

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