The ship departed San Diego Monday and will provide 1,000 hospital beds, extra doctors, nurses and other medical staff.
The USNS Mercy is expected to accept patients who do not have COVID-19. It will handle other cases to take pressure off of L.A. area hospitals as they brace for an onslaught of COVID-19 patients expected over the next few weeks.
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"That's really important for L.A. County right now because about 90% of all of our beds are already taken," L.A. County Supervisor Janice Hahn said. "We have only about 200 ICU beds available."
Assistance from the ship will free up resources, such as ventilators and intensive care units.
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"We really think the critical time for us here will be in the next few weeks, the next month," Hahn said. "We really feel like these cases will be doubling and tripling, and so we have not seen the worst of it yet."
Gov. Gavin Newsom met with Mayor Eric Garcetti and visited the ship Friday.
Newsom said the state has been working to add thousands of new hospital beds.
"We're in the process now of securing 4,000 beds of some type to prepare for the surge which we believe will start taking shape in the next week or two based upon our modeling," Newsom said. "We have not been waiting. We have been preparing."
Garcetti said he served in the Navy and had a chance to see the ship in action.
"This is a ship that is full of angels in this city of angels," Garcetti said.