The Food and Drug Administration on Tuesday authorized the first rapid coronavirus test that can be taken at home without prescription and that yields immediate results.

The test could be a vital tool in the country’s fight against the virus — especially in the months before most Americans are vaccinated. Unlike previous home tests, this version does not require samples to be sent to a lab and can be taken without doctor’s orders by anyone older than 2.

The test, developed by Australian company Ellume, is just one of several positive developments for coronavirus testing.

After months of failures, long lines and continued shortages, the country’s testing capacity is finally expected to increase rapidly in the coming two to three months, reaching many times its current levels, experts said. That reflects new technologies coming online and long-standing investments to ramp up production that are coming to fruition.

The FDA allowed the test under an emergency use authorization. The newly approved home test will cost about $30, and the first batches will be shipped out the first week of January, according to Ellume.

“It’s a big deal, and a huge step for efforts to take back control from the virus,” said Mara G. Aspinall, a biomedical diagnostics professor at Arizona State University.

But given the pent-up demand for such a test, she said, there remain questions about how much of a difference it would make unless available in large quantities and also how to prevent people and companies from hoarding such a test by buying in bulk.

Producing a coronavirus vaccine in record time was the hard part. But distributing a vaccine far and wide won’t be easy. It will take some basic materials. (The Washington Post)

In an interview, Ellume chief executive Sean Parsons said manufacturing initially will be limited to 100,000 tests per day in January with plans to increase to 1 million per day by the middle of next year. Parsons said his company will be announcing a major partnership with a major retailer — such as Walgreens, CVS or Walmart — to sell the test and create policies that would prevent hoarding by consumers. He said Ellume is in talks to supply the tests in the future directly to companies and universities.

The test uses a nasal swab to collect a sample and produces results within minutes using a plastic device similar to a home pregnancy test.

One critical feature of the new home tests: the ability to capture and report test results.

For months, at least two dozen companies have been trying to develop home tests, most of them rapid antigen tests that detect proteins on the surface of the virus. Because labs are not involved in such tests, there was no clear way to report the results. Without that data, experts warned that the country would be flying blind as it navigates the later stages of the pandemic.

Ellume’s test requires users to download an app on their smartphone to learn their test result. That app automatically sends data by Zip code to the cloud — ensuring that regional health officials can learn about positive results while keeping the data confidential, the company said.

“Today’s authorization is a major milestone in diagnostic testing for COVID-19,” FDA Commissioner Stephen M. Hahn said in a statement. “As we continue to authorize additional tests for home use, we are helping expand Americans’ access to testing, reducing the burden on laboratories and test supplies.”

While experts hailed the new test as a long-awaited development, many also worried that people may view the use of such tests as tacit permission to disregard precautions such as wearing masks or maintaining distance. They note that some rapid tests have been 90 to 97 percent accurate in detecting the virus, and that detection often depends on when people take the test.

Experts also caution that while people can take the test one day and be negative, they can acquire the virus the next day.

Last month, the FDA approved another single-use home test kit, but it required a prescription from a doctor. That test, developed by California biotechnology company Lucira Health, was expected to sell for less than $50, company officials said.

In coming weeks, more new tests are expected to be approved. Experts said that with increasing capacity, a growing need exists for state and federal officials to come up with a national strategy for how to deploy the tests more effectively and to provide federal funding for regular, dedicated mass testing in schools, hard-hit nursing homes and among essential workers.