The sailor, whose identity has not been released, died Monday at U.S. Naval Hospital Guam. He was assigned to the aircraft carrier Theodore Roosevelt, which has seen cases of COVID-19 sweep through its crew.
At least 550 sailors, more than 10% of the roughly 4,800-person crew, had tested positive for the illness as of Monday.
The sailor had been removed from the ship and placed in isolation with four other Roosevelt sailors after testing positive for the virus March 30. His name is being held for 24 hours following family notification, per Pentagon policy.
Once in isolation, the sailor received medical checks twice a day from Navy medical teams, officials said in a news release. At about 8:30 a.m. April 9, the sailor was found unresponsive during one of those checks.
Other sailors and an on-site medical team in the house where the isolated carrier personnel were staying attempted life-saving aid. He was then moved to the hospital's intensive care unit, where he later died.
The Roosevelt has been in Guam since March 27; thousands of sailors evacuated from the ship as coronavirus cases began spreading among the crew.
The Navy's handling of the health crisis onboard the Roosevelt has been surrounded by controversy. Late last month, Capt. Brett Crozier, the ship's former commanding officer, wrote a candid plea for help as coronavirus cases began to spread.
Crozier urged Navy leaders to evacuate most of the Roosevelt's crew to prevent further spread. He sent the letter to at least 20 people, including some outside his chain of command.
The letter was later published by the San Francisco Chronicle, putting a spotlight on the Navy's response to a serious situation affecting the crew of a deployed aircraft carrier. Then-Acting Navy Secretary Thomas Modly was reportedly livid about Crozier's letter ending up in the paper, The New York Times reported.
Modly removed Crozier from his position, in part to appear tough in order to please President Donald Trump, according to the Times. That was a day after Modly stood in the Pentagon press briefing room, telling reporters Crozier wasn't wrong to raise concerns about the health of his crew. He indicated that the captain would be punished only if the Navy determined the commanding officer himself had leaked his letter to the press.
Crozier's relief was unpopular with rank-and-file sailors, who could be seen in cellphone videos shared to social media gathering to see their ousted leader off as he walked off the ship. They applauded the skipper, chanting "Captain Crozier" as he left.
As health leaders across the U.S. issued warnings that young, healthy people were getting seriously sick from COVID-19, Navy leaders said the first hundred-plus cases on the Roosevelt were "mild or moderate."
"We believe that their relative health and youth is in their favor," said Rear Adm. Bruce Gillingham, the Navy's surgeon general. "We're not assuming that they won't become more ill but, so far, indications are that they will continue to be mildly symptomatic and recover without sequela."
Modly then flew to Guam, where he addressed the Roosevelt's crew. In his speech, which was later ripped by lawmakers, retired flag officers and others, Modly disparaged Crozier. He called the captain "too stupid" or "too naïve" to command the ship.
Crozier, by then, had also become infected with COVID-19.
Modly quickly stepped down from his position of acting Navy secretary following calls for his resignation from members of Congress.
The Navy has since continued testing Roosevelt sailors for COVID-19 and moved thousands of them off the carrier as the ship is cleaned and disinfected.