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 the pressure off of Los Angeles-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."
California Gov. Gavin Newsom is expected to meet Los Angeles Mayor Eric Garcetti and visit the ship Friday.
Preparations were underway before the massive ship docks.