Coronavirus-test availability is ramping up in the U.S., but in a patchwork fashion that still isn’t meeting demand, according to doctors, health-care administrators and state officials.

Some hospitals and public-health laboratories are getting test kits that allow analysis closer to the point of care, offering results in hours. Others still must send specimens to commercial labs like Laboratory Corp. of America Holdings and Quest Diagnostics Inc. for analysis, which can mean a wait of three to four days.

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