BREMERTON — The USS Nimitz got underway in Puget Sound Monday morning in a mission to eventually help relieve the Navy's thinly-stretched aircraft carrier fleet, including the coronavirus-sidelined USS Theodore Roosevelt in Guam.

Some 8,000 personnel among the 45-year-old aircraft carrier's strike group have been in quarantine and were tested for COVID-19 prior to the warship's departure. While media had reported cases onboard the Bremerton-based flattop, the Navy steadfastly denied there have been any.

“Dealing with the challenges of the COVID pandemic has been difficult, so I’m very pleased that our mitigation efforts have put us in a position to get underway,” Capt. Max Clark, Nimitz commanding officer, said in a press release on Monday. “We are all looking forward to training and operating again. I give the crew all the credit. From the beginning, they have done all that I and Navy leadership have asked them to do — face coverings, social distancing, continuous ship sanitization, testing and periods of quarantine; all executed with precision and professionalism."

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First up for the carrier is participating in a composite training unit exercise, known as COMPTUEX, that aims to fully integrate all units of the carrier strike group. That includes cruisers from San Diego, destroyers from Everett and Pearl Harbor, and air squadrons from up and down the west coast, including the EA-18G Growlers based at Naval Air Station Whidbey Island.

All personnel associated with those units will complete COVID-19 testing before getting underway or embarking in addition to having completed a fast cruise or quarantine of at least 14 days, the Navy said in the press release.

Along with quarantining and testing sailors, the Nimitz has been performing daily medical screenings and a bolstered cleaning regimen. The Navy wants to avoid another outbreak like that aboard the USS Theodore Roosevelt, which recorded 840 positive cases among almost 5,000 sailors tested. One sailor died from COVID-19 and four remain hospitalized.

The Navy reported over the weekend that another ship, the USS Kidd, now has 33 cases of COVID-19 while it is patrolling off South America. Two sailors have been flown from the ship and are hospitalized.

More:As Nimitz prepares to depart, thousands of Bremerton sailors tested for COVID-19

The 1,100-foot-long Nimitz emerged from dry dock at the Puget Sound Naval Shipyard following a year of maintenance in 2018. It has been training in the time since and is expected to stay at sea following its training for an unknown number of months. Aircraft carrier deployments have been getting longer; the San Diego-based USS Abraham Lincoln recently finished a 295-day voyage; the longest such deployment since the Korean War.

The Nimitz's timing is important. The Navy has insisted that two carrier strike groups within different hemispheres continue to patrol at all times. The USS Dwight Eisenhower has been in the Middle East and the USS Harry Truman in the Atlantic. The Truman's deployment was extended to wait for the Nimitz to go to sea, Army Gen. Mark Milley, chairman of the joint chiefs, said earlier this month.

Josh Farley is the Kitsap Sun's military reporter and went to sea with the USS Nimitz in January. You can reach him at josh.farley@kitsapsun.com.