Teams of healthcare workers from New York are now operating two testing sites in Houston.
They've set up in churches in minority communities hit hard by the virus.
The teams arrived over the weekend with 10,000 test kits.
"We got so much help, that once it calmed down we could go out and help others that helped us," said Eddie Fraser, Vice President at Northwell.
"They provided nurses and additional staff, testing supplies, PPEs," another official said.
The teams are expected to test 500 people per day at each site.
They've partnered with a lab in Houston, meaning people will get their results in just two days.
WATCH THE SERIES: EYEWITNESS TO A PANDEMIC (Episode 6 below)
Eyewitness to a Pandemic: Episode 6 - To the Streets
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