A new at-home test for the coronavirus has been approved by the U.S. Food and Drug Administration. The test will cost about $30 and will be available over-the-counter, according to the company who makes it, Ellume.

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A new at-home test for the coronavirus has been approved by the U.S. Food and Drug Administration. The test will cost about $30 and will be available over-the-counter, according to the company who makes it, Ellume. / Ellume Health

The U.S. Food and Drug Administration on Tuesday authorized the first coronavirus test that people will be able to buy at a local store without a prescription and use for immediate results at home to find out if they're positive or negative.

The test will cost about $30 and be available by January, according to the Australian company that makes it, Ellume.

The FDA had previously authorized other tests that let people avoid long lines by collecting a sample themselves at home. But those tests require people to send the sample to a lab and wait for the results. Another recently authorized test doesn't have to be sent off to a lab, but it requires a prescription to get it.

The new test is the first that people will be able to buy without a prescription at a local store and do entirely at home on their own. It takes about five minutes to collect the sample and produces results within 15 minutes.

"Today's authorization is a major milestone in diagnostic testing for COVID-19," FDA Commissioner Stephen Hahn said in a statement announcing the authorization.

The test kit includes a special swab that enables users to collect a sample from just inside their nose. Because it can be used on adults and children as young as 2 years old, the swab comes with a special adapter that shortens the length when swabbing youngsters.

Users add a few drops of liquid to the sample and place it into a small plastic device that looks like a home pregnancy test. Results are wirelessly transmitted to a smartphone app within about 15 minutes.

"This is the first test which is really designed to be a true at-home test yourself and obtain a result," Sean Parsons, the company's CEO, told NPR in an interview before the authorization.

"This could be used for people to test themselves, for example, before going to a sporting event or a concert or going to a church to decrease the chance that they spread it other people," Parsons says.

The company, which received about $30 million from the National Institutes of Health to ramp up production capacity, will be able to produce about 100,000 tests a day by January, Parsons says. By March, production should increase to about 250,000 tests a day. By June, productions should hit 1 million a day.

Testing experts welcome the authorization, but some note that the cost and limit on production capacity will restrict the impact the test will have on controlling the spread of the virus.

"It will be a game-changer, I think, to help people quickly identify if their symptoms are due to COVID," says Dr. Michael Mina, an infectious disease specialist at the Harvard T.H. Chan School of Public Health. "But from the perspective of truly stopping or massively slowing this pandemic, this test isn't designed for that."

The technology the test uses detects proteins from the virus called antigens. The most commonly used tests, known as PCR tests, detect genetic material from the virus.

Mina has been advocating for the FDA to approve much simpler, less expensive antigen tests that could be produced in the tens of millions per day.

To obtain the authorization, Ellume evaluated the test on samples from 198 adults and children in five states. The test is 96% accurate, the study shows, according to the FDA and the company.

But the FDA and others note that antigen tests tend to be less accurate than PCR tests and may miss more infected people, giving false negative results.

"What you worry about is telling somebody, 'No, you don't have COVID,' when in fact they do. And if that was the case, they could continue to spread it," says Dr. Gary Procop, a testing expert at the Cleveland Clinic.

Procop says the test may be even more likely to incorrectly say someone is infected, i.e., a false positive, when they're really not, which can prompt them to isolate themselves unnecessarily.

"We don't want to take surgeons out of surgery suites and ICU nurses out of the ICU based on false-positive results," Procop says.

In announcing the authorization, the FDA acknowledged the test's potential shortcomings but stressed the advantages of speed and convenience.

"The fact that it can be used completely at home and return results quickly means that it can play an important role in response to the pandemic," said Dr. Jeff Shuren, director of FDA's Center for Devices and Radiological Health, in the FDA's announcement.

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