Three sailors aboard the aircraft carrier USS Theodore Roosevelt have tested positive for the coronavirus, Navy officials said Monday, marking the second outbreak on the ship in a year. 

The sailors were not experiencing symptoms and were isolated aboard the ship along with people they have been near, the Navy said in a statement. None of the people in close contact had tested positive, the service said.

"The ship is following an aggressive mitigation strategy in accordance with Navy and CDC guidelines to include mandatory mask wearing, social distancing, and proper hygiene and sanitation practices," the Navy statement said. "U.S. Pacific Fleet is committed to taking every measure possible to protect the health of our force. USS Theodore Roosevelt is currently underway and remains fully operational."

The positive tests came Sunday, less than a year after the Theodore Roosevelt crew was afflicted with hundreds of cases. In that outbreak, the ship's commanding officer, Navy Capt. Brett Crozier, pleaded with senior Navy officials to allow him to move out most of the 4,800 sailors aboard, writing a memo that leaked to the media and created a furor.

"Decisive action is required. Removing the majority of personnel from a deployed U.S. nuclear aircraft carrier and isolating them for two weeks may seem like an extraordinary measure," Crozier wrote. "We are not at war. Sailors do not need to die. If we do not act now, we are failing to properly take care of our most trusted asset - our sailors."

The acting Navy secretary, Thomas Modly, then removed Crozier from command, telling reporters that the captain had "panicked." Modly flew from Washington to Guam and addressed the ship's crew afterward, accusing Crozier of either leaking the memo or being "too naive or too stupid to be the commanding officer of a ship like this." Modly then resigned.

One sailor assigned to the ship - Chief Petty Officer Charles Thacker, 41 - died in Guam of complications due to COVID-19, the disease caused by the coronavirus. Nearly 1,300 sailors - more than 1 in 4 aboard the ship - tested positive for the virus, according to a Navy investigation.

Crozier's removal was reviewed by the Navy. In June, the chief of naval operations, Adm. Mike Gilday, upheld the dismissal, saying the investigation had found that he did not do enough to stop the spread of the virus.

While numerous Navy ships have seen coronavirus cases in the past year, only the Theodore Roosevelt and the USS Kidd, a destroyer with about 330 sailors, have had outbreaks while at sea, the Defense Department Inspector General's Office said in a report released this month.

"The Navy's ability to control a COVID-19 outbreak on a ship at sea shows that the Navy is able to control the virus even if there is community spread in a ship's home port," the investigation found.

The Theodore Roosevelt's deployment last year ran from January to July. In December, it left its home port in San Diego on deployment again, in what the Navy calls a "double pump." The ship has recently been carrying out operations alongside another aircraft carrier, the USS Nimitz, in the South China Sea.