En español | Soon it will be possible to take a COVID-19 test and get results in minutes — all without leaving your house.
The Food and Drug Administration (FDA) recently gave the green light to three COVID-19 rapid tests that deliver results in real time at home, including one that will be sold over the counter without a doctor's prescription.
For months, consumers have been able to purchase test kits that allow them to collect a sample at home and mail it to a lab. But those kits typically cost more than $100, and patients have to wait a few days for the results.
The new at-home coronavirus tests are different because they're less expensive, more convenient and deliver results on the spot. Even though vaccination is starting nationwide, public health experts say at-home tests are an important tool to help slow the virus over the next few months until most Americans have the opportunity to get the vaccine.
"COVID has turned out to be so difficult to control because so much of its transmission happens from people who don't know they're infected,” said Mark McClellan, M.D., director of the Center for Health Policy at Duke University and former FDA commissioner. “The faster, easier and cheaper we can make it to find out if you're infectious, the better."
Here are the answers to some common questions about the new at-home tests:
What are the different types of at-home tests?
So far, the FDA has given what's called emergency use authorization (EUA) to three at-home tests. That means the tests haven't gone through the full rigorous FDA approval process, but the agency wanted to get them on the market quickly due to the severity of the pandemic. The tests are:
- The Ellume COVID-19 Home Test: This is the only at-home test that can be done without a prescription. Consumers should start seeing it on store shelves in some areas in early 2021, a spokeswoman said, and it will also be sold online. It will cost about $30. It delivers your results wirelessly to a smartphone app in about 15-20 minutes.
- Abbott's BinaxNOW COVID-19 Ag Card Home Test: You will order this test through a digital health platform called eMed after answering screening questions. Once you get the test, a certified guide will walk you through collecting your sample via video call. Distribution is expected to begin in January to “select states and employers,” an eMed spokesman said. The test will cost $25, plus overnight shipping. Results are available in about 15 minutes.
- Lucira COVID-19 All-In-One-Test Kit: This is the only at-home test that uses molecular technology, which can pick up very small amounts of viral genetic material. (The at-home tests from Ellume and Abbott are based on antigen technology.) The test will cost about $50, and Lucira expects to have it on the market nationwide by early spring. To get the test, you need a prescription from a health care provider who suspect you have COVID-19. It takes about 30 minutes to deliver results.
How accurate are the tests?
Data submitted to the FDA for all three tests show high accuracy rates – above 90 percent — but testing experts noted that their effectiveness in the real world will likely be lower due to user error and other factors.
"When manufacturers are preparing data to submit to FDA, they are conducting studies under very specific, highly controlled conditions that optimize the performance of the test,” said Kelly Wroblewski, director of infectious disease programs at the Association of Public Health Laboratories.
The Ellume and the BinaxNOW tests use the same antigen technology as many of the rapid tests given by health care providers. Studies indicate antigen tests are less accurate than the gold standard method used by labs called polymerase chain reaction, or PCR.
Antigen tests are most likely to be accurate when you're having COVID-19 symptoms, Wroblewski said. Common signs of COVID include cough, fever, fatigue, muscle aches, congestion, runny nose, loss of taste or smell, nausea, vomiting and diarrhea, according to the Centers for Disease Control and Prevention (CDC).
The Lucira test uses a newer molecular technology called loop-mediated isothermal amplification reaction (LAMP) that is similar to PCR. Like PCR, it works by copying the virus's genetic material until there are detectable levels.
David Pride, M.D., director of the clinical molecular microbiology laboratory at the University of California, San Diego, says that molecular tests are generally more accurate than antigen tests because they can detect the virus at lower levels, but they are still less sensitive and less specific than a PCR test done in a lab.
For any at-home test, if you have symptoms and you test positive “it's very, very likely you have the virus,” Pride said, and you should go into isolation and get in touch with your health care provider.
How confident can you be in a negative result?
A negative test can give you more confidence about going into work or visiting a family member, but experts emphasized that it's not a free pass to stop wearing a mask, practicing social distancing or taking other precautions.
"The danger is that you'll have people use these tests to say I can safely go see grandma when they may be brewing an infection that is below the limit of detection,” said Gary Procop, M.D., medical director in clinical virology at the Cleveland Clinic. “People really need to understand these subtleties, and they're not all on the package insert,” he added.
Antigen tests, in particular, are likely to miss the virus if you're early in the infection, the FDA says.
If you test negative but have symptoms, reach out to your health care provider, because there's a high risk it's a false negative, Procop said. Your doctor may order a PCR test to confirm your result.
How difficult is it to give yourself a test?
The authorized at-home tests all require you to collect a sample by swabbing your nostrils, either just inside or a little deeper, depending on the test. The good news: You don't have to insert a swab into the deepest part of your nose like some of the tests performed by health care providers.
As a general rule of thumb, “make sure you're really swirling it around and hitting skin,” Wroblewski advised. Also, avoid blowing your nose right before you take the test.
In addition to detailed written instructions, many tests include some help, either through an app, phone call or a video visit, to ensure you're doing it right and to answer your questions about your results.
In its application for FDA authorization, Abbott noted that its BinaxNOW test “was perceived as being easy to use.”
When is it better to get the test from a health care provider?
If your symptoms are severe or you are in a group at high risk of complications from COVID-19, some experts recommend getting tested by a health care provider rather than doing an at-home test.
"With COVID, your oxygen saturation counts can decrease pretty quickly, particularly if you are in a high-risk group, so you want to make sure someone is monitoring your condition,” Wroblewski said.
High-risk groups include those with cancer, chronic kidney disease, COPD (chronic obstructive pulmonary disease), obesity (BMI of 30 or higher), sickle cell disease, smoking, a weakened immune system from a solid organ transplantation, type 2 diabetes or serious heart conditions, according to the CDC.
Will insurance or Medicare cover an at-home test?
Whether you conduct your COVID-19 test at home or at a clinic, if it's ordered by a licensed health care professional who believes it's medically appropriate, then federal legislation requires your private health plan to cover the cost, said Sabrina Corlette, a research professor who studies health insurance policy at the Center on Health Insurance Reforms at Georgetown University.
Medicare Part B also covers medically appropriate COVID-19 tests when a doctor or other practitioner orders them.
However, it may be difficult to get a health care provider to order the test if you don't have symptoms or a known exposure, Corlette said. And you probably won't be able to get your insurance to pay if you pick up an over-the-counter test at your local drug store and there's no doctor involved, she said.
"If you're asymptomatic and you just want some assurance before you travel or visit a family member, your primary care provider may say you don't medically need a test,” she said. “But if you can afford $30 for an at-home test … now you can just go and pick one up.”