Good morning. Welcome to Axios today. It's Wednesday, July 15. I'm Niala Boodoo. Here's how we're making you smarter today. Small businesses are being decimated by the

pandemic and the Trump administration does a rare backtrack on foreign student

visa restrictions. But first, don't just test people for the coronavirus.

Test buildings.

That's today's one big thing.

We've been talking so much about testing people for the virus. But what about

testing buildings? If you test a building it's sort of like an early warning sign if you detect some coronavirus in

the building well then you know that the people who were in there recently might

have been exposed you can test a whole bunch of people and actually maybe even get a

head start on an outbreak.

Joanne Mueller covers transportation and industry for Axios from Detroit.

She's been looking into research on the west coast of places

that are doing real-time tests on buildings. So this company called

a viral tech and they were working with the University of Oregon so they had 18 of these

centers that were tested and in one case they had been testing every week they

had no detection of coronavirus at all and then in the third week suddenly they found it and they found it by

swabbing the air ducts which is sort of alarming because it could be spreading from room to

room and around the whole facility.

Then they could go and test all the people

and see whether any of them had coronavirus.

And it turned out four or five people actually were positive but had no symptoms.

And so they isolated those folks and within five days they started developing symptoms.

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