Nearly 2K US troops currently have the novel coronavirus: Pentagon More than 400 of those cases are sailors on the USS Theodore Roosevelt.

Nearly 2,000 U.S. service members currently have the novel coronavirus, according to new data published by the Defense Department Thursday. More than 400 of those cases are sailors with the aircraft carrier USS Theodore Roosevelt which is sidelined in Guam as the Navy continues to test each of the approximately 4,800 crew members with the ship.

The department said that of the 1,898 DOD personnel who are living with the virus, 64 are hospitalized. Another 113 have successfully recovered, while one service member has died.

The number of confirmed cases among DOD personnel -- active duty, National Guard, and reserve -- has more than doubled with each passing week. Last Thursday, the department reported just under 900 current cases. Two weeks ago, that number was closer to 300.

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Additionally, the department reported on Thursday that there are 644 current coronavirus cases among DOD civilians and contractors.

Over the weekend, Defense Secretary Mark Esper told ABC News that the Pentagon is watching the coronavirus' impact on the military's ability to defend the nation "very closely" but expressed optimism about the state of the force.

"Out of a force of two million, we're in pretty good shape right now," Esper said Sunday on ABC's "This Week."

Vice Chairman of the Joint Chiefs of Staff Gen. John Hyten echoed that sentiment in a Pentagon briefing on Thursday morning, telling reporters: "We're in pretty good shape given the crisis that we're in."

Still, senior defense officials have publicly acknowledged that there will be an impact to military readiness, though where the force is being hit hardest is becoming more difficult to track. Late last month, the Pentagon decided not to reveal the total number of service members affected in a given location where a coronavirus outbreak was occurring, citing operational security concerns.

“What we want to do is give you aggregated numbers. But we’re not going to disaggregate numbers because it could reveal information about where we may be affected at a higher rate than maybe some other places,” Esper told Reuters at the time.

An exception to that policy has been with the USS Theodore Roosevelt, the aircraft carrier sidelined by the virus after it was forced to dock in Guam because of a coronavirus outbreak. After a letter by the carrier's now-former commanding officer leaked to the media alleging his sailors could die if not properly cared for, the Navy has regularly updated press about the status of the Roosevelt.

As of Thursday, there were 416 positive cases among the ships approximately 4,800 person crew with about 1,000 tests results pending, Hyten said. One of those individuals who has tested positive is now in an intensive care unit after being found unresponsive in his room by fellow sailors overnight.

"We're praying for him and his family and his shipmates," Hyten said, confirming the hospitalization first reported by NBC News.

And the general warned that "it's not a good idea" to think that what's happening on the Roosevelt "is a one of a kind issue," adding, "To think that it will never happen again is not a good way to plan."

But the service members responding to the virus stateside also account for a number of the department's coronavirus cases.

Currently, about 46,000 service members -- including thousands of military medical personnel -- are responding to coronavirus efforts across the nation: on hospital ships, in field hospitals, and with the National Guard, risking their own lives to help health facilities overwhelmed with patients.

On Wednesday, the head of the National Guard Gen. Joseph Lengyel said that 349 Guard personnel had tested positive for the virus. It was also a National Guard soldier who was the first and only service member to pass away from the illness.

Army Captain Douglas Linn Hickok, 57, served in a National Guard Medical Unit based out Seagirt, New Jersey. A graduate of Cornell Medical School, Hickok enlisted in the Guard in 2009 but had been working for the last several years as an orthopedic physicians assistant at a clinic in Pennsylvania, according to his obituary.

His sister, Mary Hickok, told ABC News that "Doug" was "fearless and kept serving others, even at his own risk!"

"He loved to travel and take us to parks, museums, battleships, military bases, movie theaters, beaches, and restaurants," his daughter, Shandrea Hickok, said.

She described her father as caring and devoted with a "sense of wonder and zest for life."

"I know Doug would want people to know how much he loved his family, his Country and its Constitution, and his faith, serving for two years in Spain as a missionary for the Church of Jesus Christ of Latter Day Saints," Mary said.

"My brother would not want people to be scared of this virus that sadly took his life. He would want people to be safe but have hope in their lives and live fully because no one knows when they're going to pass on."

Douglas passed away on March 28 and is survived by his two children, first wife, father, sister, two brothers, and 15 nieces and nephews.

What to know about coronavirus:

How it started and how to protect yourself: coronavirus explained

What to do if you have symptoms: coronavirus symptoms

Tracking the spread in the US and Worldwide: coronavirus map