The COVID testing FAQ: What to test, when to test, and what to expect:- Every week we answer the most frequently asked questions about life during the coronavirus crisis. If you have a question that you would like us to consider for a future post, please email goatsandsoda@npr.org with the subject: “Weekly Coronavirus Questions”. View an archive of our frequently asked questions here.
In an ideal world, the United States would be inundated with COVID tests. Anyone exposed to COVID could self-test and/or go to a laboratory or clinic for testing if needed.
But right now, self-testing is scarce in many parts of the country. The Biden administration has pledged to distribute 500 million rapid tests “within weeks,” White House Coronavirus Response Coordinator Jeff Zients said Wednesday, but few other details have been announced.
And test makers are ramping up production, so the hope is that at some point, even if no one can say exactly when you won’t see those “no tests available” signs at your local pharmacy or you’ll have to wait a week or more. for tests ordered online.
Additionally, the Centers for Disease Control and Prevention changed their testing guidelines in the wake of the rise of omicron in the United States, and public health researchers are critical of some of the recommendations.
The end result is a lot of confusion about the tests and a lot of frequently asked questions. Here are some answers to questions you may have about the COVID test.
What types of COVID tests are there?
There’s the rapid, do-it-yourself home test, which involves swabbing your nose and takes about 15 minutes to display a result on a test strip provided in the kit. These cost about $20 for a package of two tests. They’re known as “antigen tests”—antigens are basically the proteins from the virus that the rapid tests can identify.
Then there’s the PCR test, performed in a lab or clinic. PCR stands for pa olymerase chain reaction, which is a technique for amplifying a small amount of viral DNA. Depending on how busy your local technicians are, you may get PCR results in one day or it may take several days. A PCR test typically costs around $ 150 without insurance.
Are there any other types of tests?
There is a third type of test: a blood test that looks for antibodies after you’ve been sick, and some samples can also be taken from a finger prick at home and sent to a lab. But they are not used to diagnose
COVID-19. Does insurance cover testing?
Most insurance policies cover PCR and rapid tests administered by health providers. The Biden administration has announced a plan for insurance companies to reimburse at-home tests starting this month, but details are not yet
available.
What’s the difference between antigen and PCR tests?
PCR testing is much more accurate in identifying infections because it can amplify traces of the virus; in other words, even if you have a small amount of virus, it can detect it. So you can tell if you are infected even a day after developing what appear to be symptoms of COVID or a few days after exposure to someone with COVID.
Antigen tests do not increase the amount of virus in the sample, so a high enough viral load is required to be positive. As Susan Butler-Wu, an associate professor of clinical pathology at the University of Southern California’s Keck School of Medicine puts it: “It’s a test to [determine if you have] a lot of viruses.” Therefore, you can test negative on a home test even if you are infected, for example at the beginning or end of your illness when you don’t have many viruses.
So which exam should I go to?
The most pressing question, Butler-Wu says, is, “What test can you take?” If you have symptoms and have likely been exposed to the virus through travel or socialization, a positive antigen test is likely sufficient proof that you have the virus, says Dr. Abraar Karan, an infectious disease doctor at Stanford University.
As for PCR tests, their availability depends on the demand in your community. Some testing facilities are overwhelmed, with few appointments available and long waits, even if you can get an appointment. And it can take several days to get the results of a PCR test.
What should I do while waiting for the PCR test results?
While waiting for the test results, if you have symptoms, you should act as if you tested positive and are in quarantine. If you’ve been exposed but have no symptoms, the CDC says you can go out wearing a proper protective mask if you are vaccinated and boosted. Those who are not vaccinated should be quarantined after known exposure until test results are available.
When should I get tested and how often?
Of course, the answer depends on whether you can be tested and what you are using it for. Tests can be used to tell you if you have COVID, for example, if you have symptoms or have been around someone who tested positive. And they can also be used as an extra precaution before socializing (which we’ll talk about in a couple of questions).
If you’ve been exposed to someone with COVID, you should self-screen. But not immediately. “If you have been exposed, wait a few days because the test could be immediately negative,” says Karan. After waiting, “then we will be able to detect viruses”. The Centers for Disease Control and Prevention recommend testing when symptoms develop or, if no symptoms show, 5 to 7 days after exposure.
This would give the body enough time to develop a viral load that can be detected by a test. With the omicron variant, there have been reports of negative rapid tests during the first or two days of symptoms. So even if you are showing symptoms, you may want to wait a day or two to get your first test, especially if you have a limited supply of tests.
How many tests do I need to do?
At least two. Why try twice? Home tests are more accurate when you use them in series, at least two over the course of a few days. And if you have a limited supply of home tests, we recommend aiming for the time when you are most likely to get an accurate result, such as day 5 and day 7 after exposure.
To be absolutely honest, these tests must absolutely be used in series. They don’t have the sensitivity to be used all at once if they’re negative, ”says Butler-Wu. “By repeating this, you allow the virus to grow further to the point, essentially, where you can now detect it.” “If that test is negative, all it tells you is: right now, you don’t have a lot of viruses on you,” Karan says.
Do I have to take the test before I see people?
“If you’re going to visit Grandma or something, yeah, I’d probably take a short quiz first,” Karan says. “Or if I go somewhere where there are a lot of people. If I’m contagious that day [and I don’t know], I could infect tons of people.” A positive test result will tell you.
cancel their plans and stay home and isolate themselves. But the negative results don’t mean it’s time to take off your mask in social contexts. Rapid tests can be negative before a party and positive during a party just a few hours later, even if you are vaccinated and boosted.
“To say the negative test means being indoors without a mask, I think it needs to be rethought, soon,” says Butler-Wu.
“Omicron has completely changed the game,” she says. “We know from Christmas evenings that happened in European places that those exact scenarios occurred: people vaccinated, negative tests and there was still a spread.
” If I find negative, how accurate are the negative tests? There can be false negatives, especially soon after exposure when there isn’t much virus in your body, or if the virus is replicating somewhere other than where the sample was taken, for example, in the throat instead of the nose. That’s why you should try at least twice.
According to a pre-micron study, the Abbott BinaxNOW antigen test was 92.6% accurate in detecting the virus in symptomatic people and 78.6% in asymptomatic people, compared to PCR results in cases where people had a viable virus. It is also possible to get a false negative from a PCR test.
“Any test is a snapshot of what is happening in the part of your body that was sampled at the time. That’s all it tells you, “Butler-Wu says. “So, yes, PCR is more sensitive in that it can detect lower amounts of the virus. But if you’re in the very early stages of incubating an infection and haven’t reached what we call the “limit of detection,’ that too, can be negative. “
What happens if I test positive?
When you test positive, you should isolate yourself for a minimum of five days and wear a mask for five days after that, according to the CDC. If you have the quick tests, you can use them after five days to see if you are still positive, which would mean you need to keep isolating yourself.
If you have been tested in a clinic, the results will be reported to the local public health department. If you test positive on a home test, you should notify the health department so they can track how many cases your community has.
Are there ever false positives?
The research found that false positives are rare in PCR tests and usually occur due to contaminated samples, according to the research. A false positive on an antigen test is possible but quite unlikely if the test is done correctly, Butler-Wu says, especially if you develop symptoms and know you’ve been exposed to someone with COVID.
And many people are exposed at this time of widespread use to the omicron and delta variants. If “there’s a lot of COVID and I’m symptomatic, I’m probably a true positive,” says Butler-Wu. If you think you have a false positive from a home test, you can get a confirmatory PCR test if you can find one. “If your CRP is negative, your rapid test may have been a false positive,” Karan says. “If you can do it, fine.”
In what other case are PCR tests recommended?
If you are at risk of serious illness, you should get tested in case you need COVID medications. And some workplaces and schools require a negative PCR test to return
