We can finally test for the coronavirus at home — here's how it works

After weeks of contentious back and forth, the first at-home coronavirus has arrived. On Tuesday, the Food and Drug Administration approved a coronavirus test that can be mailed to patients' homes – a big step that will help scientists understand how many people have the coronavirus, and who may be at risk of spreading it.

In early March there were a number of at-home coronavirus tests created by startups like Carbon Health, Nurx, and Everlywell. Those tests were rushed to market under the FDA's emergency use authorization, which allowed manufacturers to fast-track their products to meet our dire need for testing.

However, as that market exploded, the FDA clarified that the agency did not authorize these tests and that they couldn't stand by their accuracy — meaning that none of these companies would actually be able to send their tests to people's homes.

This new test, called The Pixel by LabCorp COVID-19 test has actually earned the FDA's stamp of approval. Though it is still technically authorized under the Emergency Use provision, FDA commissioner Stephen Hahn said that the agency had worked with LabCorp to ensure that these tests are both accurate and safe.

"With this action, there is now a convenient and reliable option for patient sample collection from the comfort and safety of their home," Hahn said in a statement Tuesday.

Experts fighting the coronavirus have repeatedly told Inverse that testing is one of the key issues stopping us from returning to normal. Here's what we know about how this new, at-home test can work.

How do you get an at-home coronavirus test?

For now, LabCorp is prioritizing sending tests to healthcare workers or first-responders who are actively fighting the coronavirus and have developed symptoms as a result.

The rest of us will be able to get their hands on one of these kits, which cost $119 each, "in the coming weeks" according to the company's release.

But even in the coming weeks, you won't be able to simply order the test online. A healthcare provider will first have to recommend that you get tested.

Annie Sedgwick, a spokesperson for LabCorp, tells Inverse that the tests will be available in all 50 states, but that in New York, New Jersey, Maryland, and Rhode Island, state laws prohibit individuals from ordering their own lab tests. That means you'll have to consult with a doctor before you order a test (which must be done according to test protocol anyway).

From there, the website will ask you to fill out a questionnaire before you are allowed to order a test.

How do you use an at-home coronavirus test?

These tests are intended to check whether you're currently positive for the coronavirus using a nasal swab. When done at a doctor's office, this requires using a long swab that goes to the back of the nose or throat.

This at-home test uses a Q-tip-style nasal swab. Importantly, you should not go very deep into the nose when using this at-home test, according to LabCorp's website. Instead, stick the Q-tip up your nose just until the top disappears, and swirl it around the inside edge of the nostril at least three times.

You can find a fully illustrated instruction manual here and a video guide to ensure you are swabbing correctly

Then, you mail the sample off to the lab, where scientists will search for signs that the coronavirus is inside your body. Importantly, this test reveals whether you currently have the virus, not whether you have had it before and recovered.

LabCorp is also working on an antibody test that is intended to test whether you've already had the virus. As Reuters reported on Wednesday, doctors will be able to direct asymptomatic patients to LabCorp's 2,000 patient testing centers (this test can't be done at home, for now) on April 27.

What happens if I test positive for Covid-19?

You should ask the doctor who authorized your at-home test about what to do, should you test positive. However, as the patient fact sheet notes, there is a chance that you will be asked to isolate yourself. That means you should not see anyone until you are no longer sick.

That's ultimately a good thing. The more people who test positive for the virus and self-isolate (even if they are not symptomatic), the more we can hinder its spread and hopefully return to some version of normal life.

What about false positives and false negatives? — As with any test, there is a possibility that a result will be a false positive (which means you test positive for the virus, but don't actually have it). There is also the chance of receiving a false negative (you test negative but still have the virus).

The FDA requires that all Covid-19 test manufacturers run their tests on 30 positive coronavirus samples and 30 negative ones. For the FDA to consider authorizing a test, the company has to show that it can detect 95 percent of positive cases (a measure called sensitivity) and 100 percent of negative cases (called specificity).

Some scientists have expressed concerns that the FDA, in an effort to speed along new tests, has lowered their standards too much. It typically takes months to prove that a test can hit those benchmarks.

LabCorp's patient fact sheet acknowledges that there is a chance that false positives and false negatives can happen.

The LabCorp patient FAQs page says there is a "very small chance" of a false positive happening, but that your doctor will help you decide what the best course of action is.

How many of these tests exist — and why is testing so important? — Sedgwick says that 60,000 of these testing kits have already been made.

Still, by tracing the spread of the coronavirus, scientists hope we may be able to eventually relax some of these social distancing measures. Right now we test an average of 146,000 people per day for the coronavirus.

To get back to normal, we will have to test between 500,000 and 700,000 per day, The New York Times reported on April 17. Those 60,000 kits will be helpful, but we need far more testing to close that gap.

This at-home test, should it be able to fill that void, could get us started on that path.