If we’re going to slow down the coronavirus pandemic and get people out of their homes and safely back to work, experts agree part of what’s needed is widespread testing. Right now, you can only get a test at a hospital or clinic, however, so widespread testing would potentially expose more people to the virus. At-home diagnostics could provide additional testing with less risk of sharing sickness — and labs and startups are hurrying fill that need.

“In the situation where a person would like to know if they’re positive so they can make [distancing] decisions, but they’re not severely ill enough that they need to seek medical attention, a test can provide peace of mind,” says Emily Martin, an epidemiologist at the University of Michigan School of Public Health. “That’s where these [at-home tests] can be very useful. Even for influenza, the health system simply does not have bandwidth to have medically-provided tests for everybody who just wants to know.”

In late March, the FDA curtailed marketing efforts by a few eager startups, warning consumers the agency had not authorized any at-home tests, and even calling the tests that were being billed as available “fraudulent.”

Rolling Stone reached out to five scientists and doctors — including some working for companies developing tests — to sort out the status of at-home testing for COVID-19. All agreed the main challenge is regulations. As of this writing, the FDA has not approved a single at-home testing kit for COVID-19; for that to happen, companies marketing tests have to prove the tests work — that a user can follow instructions, collect a usable sample, that the sample won’t be damaged in the mail if it’s being sent to a lab, and that the results will be as accurate as the tests done by a doctor on a patient in a hospital.

The raging public health emergency has prompted the FDA to allow some flexibility and accelerated approval avenues for tests that are performed by healthcare professionals and processed by experienced labs, but those allowances so far haven’t been extended to at-home testing, due to a higher risk of inaccurate results, an agency official tells Rolling Stone. For some in the medical field, this struggle is part of a larger clash between innovation and regulation. “This is not the only virus we’d like people to stay home for,” says Martin. “If we could have that ability to do [at-home testing] for the flu or other viruses, that would be great, but it’s just a huge regulatory hurdle.”

How would at-home testing work?
There are two types of home COVID-19 tests being talked about right now. One is just like the test that’s been performed for months now in healthcare settings, known as a PCR test, where a nasal swab is taken from the patient and tested for the genetic material of the virus itself. In the at-home version, patients collect the sample themselves, then mail it in for lab analysis, and get their results a day or so later.

While initially the CDC was recommending a deep (and reportedly uncomfortable) “nasopharyngeal” swab, which goes up the nose to the back of the throat, the latest guidelines allow for a shallower, inside-the-nose swab in both nostrils. The same guidelines even allow people to swab themselves, so that healthcare professionals can keep their distance, say, in a drive-through testing line. It’s not such a huge leap from there to imagine people swabbing their nostrils in their own homes.

This test would still involve a doctor to authorize the kit being sent to a patient in their home, and then to discuss results with the patient. “I think startups have done themselves a disservice saying it’s a direct-to-consumer model,” Dr. Shantanu Nundy, a physician, community health advocate, and chief medical officer at Accolade, a population health company. “People have an impression that they were thinking of sending test kits without a physician or provider in the loop. None of them had that intent.”

In fact, Nundy adds, consumers should avoid any test sold without connecting the user to a doctor, if such a test were to be approved. “These tests have a false negative rate, meaning sometimes it appears you don’t have the coronavirus but there’s still a small chance you do,” he says. “It’s important to have a physician explain those findings to the patient, as they may still need to self-quarantine or be tested again later.”

The other type of test, known as a serologic test, looks for antibodies that appear soon after infection, as the immune system fights the virus. They remain in the body after the virus is gone, and likely indicate some level of immunity. The first U.S. version of this test, which is performed by healthcare professionals in hospitals or clinics, was approved by the FDA earlier this month.

Several companies, including home-diagnostics startup Scanwell, are working on getting the same kind of test approved for at-home use. In Scanwell’s version, a doctor orders the test by overnight mail for a patient after a consultation, then the patient pricks their finger and mixes a drop of blood with a solution in a test cassette. After 15 minutes, they use a smartphone app to take a picture of the results which will be interpreted by a doctor who will contact the patient with next steps.

“The doctor or nurse will use CDC guidelines to decide who should be getting tested,” says Scanwell Chief Medical Officer Jack Jeng. “As things progress, we anticipate the people who can get the test will expand, but right now, given the expected demand for testing services, we want to start with the highest-risk patients.”

At least one company, LetsGetChecked — which sells home tests for sexually-transmitted infections, Celiac disease, and more — already has a two-in-one PCR and antibody test kit approved for use by healthcare workers in professional settings, and the developers are seeking FDA approval for an at-home kit, too. Chief Medical Officer Robert Mordkin points out that since antibodies appear while an infection is still active, using both tests could help promptly establish whether a person is still contagious, with antibody test results appearing in 15 to 20 minutes. “Let’s say somebody’s antibody test is positive, but you do the swab and it’s negative,” Mordkin says. “That would suggest they had an infection but they’ve now cleared that infection. There’s real power in that.” In theory, a healthcare worker who was infected could return to the front lines of treatment knowing they are not spreading the virus, and, pending further research, without fear of being re-infected.

Large-scale antibody testing could be helpful when it comes to restarting the economy and getting people back to work. Although uncertainty remains as to the length of immunity and the possibility of reinfection after having COVID-19, the antibodies produced during infection by other types of coronaviruses give someone immunity for months, or even years. “We could send at-home antibody tests to every household in America, and if the test comes back that you’re immunized already, you can go right back to work or school,” says Nundy. “That’s an intriguing idea.”

Are these tests legit?
Most of them likely are. “I’m sure there are so many tests being made by startups right now, some of them probably are junk,” Martin says, but notes that FDA process is designed to weed out any that are inaccurate. “There are ways to figure out which tests are working and which tests aren’t, so there are reasons for all of these rules and regulations.”

According to Jeng, Scanwell’s test kit is licensed from a Chinese manufacturer whose product was already approved by China’s version of the CDC. (Martin notes it is not unusual to see tests approved in other parts of the world and not the U.S. “It’s just the way our approval system works, and the speed at which it runs,” she says.) For PCR tests, Nundy points out that many at-home test companies would be sending samples to the same established labs that are already analyzing similar tests from hospitals.

Nundy is more concerned about the potential for over-testing than truly “fraudulent” testing. “You can imagine a service — and I’m being extreme — that says hey, even if you call about back pain, we’re sending you an at-home [coronavirus] test,” he says.

“The test wouldn’t be scammy, it just wouldn’t be appropriate for that patient to get that test.” The trouble with over-testing, in addition to using up medical resources unnecessarily, is you may be looking for trouble where there is none. Nundy says it’s the same reason we don’t give everyone CT scans at check-ups. “It will find things in your body that aren’t necessarily there, and the next thing you know you’re getting biopsies and stressing yourself and your whole family out,” he says.

Overall, there’s no reason to believe at-home testing cannot be done as effectively as it is in hospitals, but the FDA needs to approve it. “It’s not a technically challenging issue,” Martin says. “It’s a regulatory issue.”

Why is it so hard to get FDA approval for home testing?
For diagnostic tests, companies have to run trials to ensure that they work. In the case of at-home testing, one of the things they’d need to prove is that patients can follow the directions and get as good a result as if it were administered by a professional. The FDA decides on a case-by-case basis what type and extent of clinical trial is needed. During this pandemic, the FDA has issued Emergency Use Authorizations to fast-track the release of some COVID-19 tests, including, recently, the newly-approved antibody test. So far, though, EUAs have not been granted for any type of tests that would be administered at home.

Beyond the time it takes to run trials, regulatory red tape may still be an issue. “Just because you develop a test that works and you can validate it doesn’t mean that our regulatory environment is going to support it,” Martin says. According to Martin, when the FDA approves a test for use in the U.S., they also specify in what scenarios it can be used; patients testing themselves at home and sending in samples is not one of them. “The FDA would have to change regulations, basically, to let that be allowed,” she says. “Any sort of mailing or shipping of a specimen would violate approval of the current test.”

The FDA official says the agency would simply need to approve an at-home test, and to do that, they need data from test developers. Their concern is an inaccurate test could cause more harm than good.

Is the FDA being overly careful?
It depends who you ask. Nundy believes the process should be accelerated, perhaps in part by pooling clinical trial results from established labs, rather than having each lab do its own full trial. “This is a national emergency and I think the FDA is being far too cautious,” he says. “We have data to assure safety and efficacy…. We need the FDA to accept that data and allow the innovation community to do what it is we’re able to do.”

Alex Greninger, an assistant director of the University of Washington’s clinical virology lab, which received approval via EUA for one the first COVID-19 tests in the country, says it makes sense that the FDA is waiting for case-by-case data for at-home testing. “It’s not unreasonable for the FDA to look for this data given the crush of demand and various suppliers looking to meet that demand,” he says. “Ensuring sample integrity and test integrity are not small items.”

How long could this take?
No one is certain. Jeng is hopeful about the possibility of gaining approval through the accelerated EUA process. “If FDA approves our testing service under the EUA, this is something that can be available within the next two months,” he says.

Greninger also says we should expect a shift in the next four to six weeks toward at-home testing, given its advantages: “No PPE usage, less risk of occupational exposure, last-mile logistics already solved.”

Martin thinks the wait will be a little longer. “If it’s feasible, I could see that happening probably not during this acute phase of the epidemic, but it could be very useful during future months, as we start to ease restrictions and people go back to work and it becomes important to try to figure out who’s infected and who isn’t so we can open schools and stop the spread of it from coming back.”

The representative from the FDA says once a developer submits data showing accurate, reliable results, approval can take less than one day.