WASHINGTON – The coronavirus outbreak aboard the USS Theodore Roosevelt escalated Wednesday as more sailors tested positive for the virus and U.S. Navy officials scrambled to respond to the desperate evacuation plea from the aircraft carrier's captain.

As of midday Wednesday, 93 crew members had tested positive for the virus, and 593 tested negative, Thomas Modly, acting Secretary of the Navy, told reporters during a briefing Wednesday. There are approximately 5,000 crew members on board.

"None of them are seriously ill," Modly said.

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He said 24% of the crew, or about 1,200 sailors, had been tested so far, and Navy officials were trying to take hundreds of sailors off the ship for isolation and monitoring.

"We already have nearly 1,000 personnel off the ship right now. And in the next couple of days, we expect to have about 2,700 of them off the ship," Modly said.

But he also said the Navy could not leave the vessel empty, because it's loaded with weapons and a nuclear reactor, among other dangerous materials.

"It has munitions on it. It has expensive aircraft and has a nuclear power plant," Modly said. "It requires a certain number of people on that ship to maintain the safety and security of the ship."

He said the Navy would have to keep about 1,000 sailors on board to keep the vessel's critical functions operational and conceded officials were faced with "a delicate balance" between the safety of the crew and the Navy's mission.

"You can't leave a nuclear reactor there, running without anybody on the ship," he said.

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The infection numbers come two days after Navy Capt. Brett Crozier sent an urgent letter to the U.S. Navy, asking officials to evacuate and isolate the crew as cases of coronavirus infection increased on the vessel.

Crozier said "decisive action" was required to prevent deaths from the coronavirus, and that the sailors on board were currently unable to comply with Centers for Disease Control and Prevention guidelines to keep them safe because of the ship's close quarters.

The Navy first reported on March 24 that three sailors had tested positive and been airlifted to a hospital in the Pacific. One day later, five more sailors were diagnosed. By March 26, as the ship docked in Guam for a scheduled visit, that number had jumped to 23 sailors.

"We are not at war, and therefore cannot allow a single Sailor to perish as a result of this pandemic unnecessarily," Crozier wrote in Monday's letter.

"Due to a warship's inherent limitations of space, we are not doing this. The spread of the disease is ongoing and accelerating," he added.

The Navy announced last week that it would conduct testing on all of the approximately 5,000 sailors aboard.

It's not clear why the service has tested only 24% of the crew so far. Officials said there has also been a delay in getting results back, in part because the samples had to be shipped to a Defense Department lab.

Modly and other Navy officials said they were trying to find hotel rooms and other housing options in Guam for evacuated sailors.

Asked about Crozier's letter, Modly and others expressed concern that his letter had been leaked to the media and suggested there had been some sort of "communication's breakdown." The San Francisco Chronicle first reported on the contents of the captain's missive.

"It's disappointing to have him say" that the Navy was not taking care of its most trusted asset: the sailors, Modly said.

"However, at the same time, I know that that's not the truth," he said. "We've been working very, very hard with the ship with this command structure to ensure that that's exactly what we're doing. It's our priority. We need those sailors to be safe. We need them to be healthy. And we need that ship to be operational."

Navy Admiral Mike Gilday said Crozier has an "extraordinary responsibility of command" and is accountable for the health and well-being of the 4,865 sailors aboard the Roosevelt.

"He takes it very seriously," Gilday said. So if he believed the Navy wasn't acting urgently enough, "then absolutely we need to know about that and ... we need to adjust."

At a White House briefing Wednesday evening, Gilday said the Navy was taking other precautions to prevent infections on other vessels. Among other steps, he said sailors would go into quarantine for 14 days before deployments or training exercises, to identify any infected personnel before they board a Navy vessel.

Modly conceded it was a difficult and ever-changing situation. "A lot of this is we're adjusting on the fly," he said.

Contributing: Jeanine Santucci

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