US Navy hospital ship sent to support COVID-19 fight in LA leaves after treating just 77 patients in 7 weeks

• The US Navy hospital ship USNS Mercy left Los Angeles on Friday after a seven-week deployment.
• During its time in LA, the ship treated just 77 patients, and now it is returning to its homeport in San Diego.
• Around 60 medical personnel assigned to the ship will stay behind to provide care at skilled nursing facilities.
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The US Navy hospital ship USNS Mercy is departing Los Angeles after treating only 77 patients in seven weeks, US Northern Command announced.

The ship left Los Angeles early Friday morning.

The Mercy arrived in Los Angeles on March 27, just a few days before sister ship USNS Comfort arrived in New York City. The two ships were sent to serve as a "relief valve" for local medical facilities battling COVID-19 in hard-hit areas by treating patients suffering from other ailments.

"By serving these emergency patients away from the hospitals, beds will be opened up all over the city for those who are infected," President Donald Trump said of the Comfort before it left for New York in March. "This ship can handle a lot of people, so it will open capacity all over the city."

The Comfort was later reconfigured to treat COVID-19 patients, but even after its mission changed, it remained underused. The ship left New York City on April 30, exactly one month after it had arrived, after treating 182 patients.

The Mercy, however, was not retasked to treat COVID-19 patients. Instead, it provided medical, surgical, and trauma care to other patients.

The Mercy treated a total of 77 patients before it stopped receiving patients on April 30 at the direction of FEMA and US Northern Command. The ship discharged its last patient on May 5.

A Navy official told Insider on May 7 that the Navy is working with various agencies "to get the ship underway." The question at that time was whether the Mercy would go back to its homeport in San Diego or be sent somewhere else.

US Northern Command said in a statement that the Mercy will return to Naval Station San Diego, where it will remain in a ready status should it be needed elsewhere.

The large hospital ship will leave behind 60 of its personnel to provide care at skilled nursing facilities in California in support of FEMA, as well as state and local healthcare providers.

During the Mercy's deployment to Los Angeles, at least seven members of the ship's medical personnel contracted the coronavirus, but everyone who got sick has since recovered. The Comfort experienced a similar situation during its time in New York City.

Each hospital ship — previously supertankers that were converted into the largest hospital vessels in the world — can, if necessary, be configured to treat hundreds of patients, but they both consistently operated under capacity as there was less a demand for their services than initially expected.

"We were able to be a relief valve in anticipation of something that didn't quite get as bad as anybody thought that it might," Capt. John Rotruck told the Los Angeles Times earlier this month.

While Los Angeles county remains one of California's most affected areas with more than 35,000 confirmed cases, it has not seen anywhere near the more than 100,000 cases in New York City.