Sara Polon spends $800 dollars each week on coronavirus tests for the staffers at her Washington, D.C., business, but sometimes the test results don’t come back for weeks.

Polon, 43, owns Soupergirl, a small soup company that has managed to stay open during the pandemic. Polon wanted to reassure her 30 full-time and part-time employees that she was trying to protect their health, so she’s been covering their weekly coronavirus tests since early June. But the national lab where the results are processed has significant backlogs.

“If I’m getting results 2 1/2 weeks later, I might as well just take that $800 and flush it down the toilet,” Polon told NBC News. “I’m just at the mercy of these national labs, and it’s petrifying.”

What Polon needs is a cheaper test with fast results that her employees could use at home, experts say. To ease the overwhelmed testing system, a growing number of doctors are calling for the U.S. to overhaul how it detects COVID-19.

Epidemiologist Dr. Michael Mina of Harvard University T.H. Chan School of Public Health wants the U.S. to support more antigen tests, which can offer faster results with less lab work. Doctors already use antigen tests to diagnose infectious illnesses like influenza or strep throat, and while they are not as sensitive as the polymerase chain reaction, or PCR, test, widespread use of them could ease lab delays and help control “burning epidemics” across the U.S., Mina said. Mina describes them as “transmission blocking tests” because they could identify people who are most infectious and likely to spread the virus.

The PCR test is considered the most accurate way to detect positive cases, but specimens need to be shipped to a lab and require a slew of supplies, including swabs and chemicals, which are in short supply.

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“If you’re testing somebody and giving them a result back a week later, the utility of that test is essentially zero,” Mina said. “I envision a day when everybody can go on online and order your package of 50 tests for $50 that’s gonna last you a month or two, or two or three months.”

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The Food and Drug Administration has granted emergency use authorization to two point-of-care antigen tests made by Quidel and BD. These tests, while quick and accurate, require expensive machinery that would make it tough for users to perform at home on a regular basis.

A number of companies have developed at-home diagnostic tests that won’t require machines, labs or long turnaround times and are waiting for regulatory go-ahead. In the coming weeks, E25Bio — a Cambridge, Massachusetts, company that has made rapid diagnostics for other viruses like Zika and dengue — is planning to request authorization from the FDA for a coronavirus paper-strip test. In April, Mammoth Biosciences published results of its paper-strip test in the journal Nature Biotechnology that showed it was nearly as accurate as PCR.

Because an antigen test requires a higher level of virus present in the body to test positive, it can miss some cases. Critics warn that because antigen tests aren’t as sensitive as PCR testing, there is greater possibility of higher rates of false positives or false negatives.

In fact, this week, Ohio Gov. Mike DeWine said he had tested positive for the coronavirus through an antigen test. DeWine later tested negative through PCR testing.

Dr. Rochelle Walensky, chief of infectious disease at Massachusetts General Hospital, said DeWine’s experience shows the risks of rapid antigen tests.

“Unfortunately, I worry a lot about false positives with these,” Walensky told NBC News via email. “To date, most positive tests have not been confirmed with a follow-up test, so we don’t know exactly how many false positives occur.”

Even with the risks, however, Walensky sees rapid testing as a way to open schools and businesses safely before a vaccine is available.

A false positive test, while not as concerning as a false negative, could cause emotional stress or difficulties for people who try to self-isolate when they don’t have the virus.

But a false negative shouldn’t be overly concerning, said Dr. Ashish Jha, professor of medicine at Harvard Medical School, said.

“We know that a lot of false negatives happen when you have the virus, but you’re not super infectious,” Jha said. “What I care about is not identifying everybody with the virus. I care about identifying everybody who’s infectious who could spread it to other people.”

Dr. Steven Woloshin, a professor at the Dartmouth Institute for Health Policy and Clinical Practice, said more data is necessary before implementing widespread use of antigen testing for the coronavirus.

“In theory, frequent, repeated use of these tests could overcome their lower sensitivity [which could lead to false negative results]. But we really need some proof,” he told NBC News via email.

Antigen tests wouldn’t replace PCR testing completely, Mina said, but could be rolled out to areas with spikes in cases or be used by businesses and universities where there is a demand for frequent, rapid testing. Mina and his colleagues published a pre-print that showed frequency of testing and turnaround time are more important than sensitivity. A preprint is a study that hasn’t yet undergone a rigorous peer-review process required for publication in medical or scientific journals.

On Thursday, Dr. Brett Giroir, who oversees coronavirus testing for the Trump administration, said rapid, or point-of-care, testing will soon play a major role in the response to the virus.

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“Every nursing home is going to have it. Most ERs are going to have it. And a lot of schools are going to have point-of-care testing, not so much to screen children, but if someone’s sick, they know right there whether they have COVID or not,” Giroir said.

Meanwhile, there is some action to make the tests more widely available. DeWine was recently part of a joint effort with governors of five other states to purchase 3 million antigen tests to ramp up testing capacity.

But as efforts to ease the nationwide testing backlog sputter along, business owners like Polon are left wondering how to keep their employees safe.

“I started this testing program so I could have knowledge and information about the health of my team,” she said. “But I feel that I’m even more in the dark than before.”



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