Why PCR is better than Rapid Antigen Testing
When you find out you’ve just been exposed to COVID-19, it’s important to take action and get tested so you can protect others. There are many types of COVID-19 tests you can take – but if you’re not showing symptoms yet, what is the best COVID-19 test for you?
Do I need to test if I’m pre-symptomatic or asymptomatic?
According to Harvard University, a person with COVID-19 may be contagious 48 hours before they start showing symptoms. The same article referenced a study from JAMA Network Open, which found that almost one out of every four infections may be transmitted by asymptomatic individuals. If you aren’t experiencing symptoms, you’re less likely to take extra precautions to prevent exposure to others.
In another study, researchers found that there was no difference between the viral load peaks – the time when the highest amount of the virus is in your body – in patients with or without symptoms.
Simply put, you can be showing no symptoms and be just as capable of spreading the virus as someone who does show symptoms.
So when is the right time to get tested if you’re not showing symptoms? If you test too soon, you may get a false negative test result. The CDC reports that the virus has a median incubation time of four to five days, and a person who was infected with the virus would likely test positive 3 to 5 days after contracting it. With that in mind, let’s look at what testing options are available.
What about rapid antigen testing?
Antigen testing works by looking for proteins on the surface of the virus, which can provide results in a lab or doctor’s office in just 15 minutes.
But that speed comes at a cost: antigen testing is much less sensitive than the RT-PCR test.
Because the antigen levels in your body are lower before you show symptoms as well as late in the course of infection, your levels may be below the limit of detection of virus of the test, according to the CDC.
That means you could get what’s called a false negative result – i.e. your test was negative, but you’re actually infected with COVID-19.
One CDC study found that antigen test accuracy dropped to 41.2 percent for individuals who weren’t experiencing symptoms.
A real-life example of antigen testing failure occurred in the White House in October 2020. At the time, the White House largely relied on antigen testing to monitor for COVID-19. According to the New York Times, at least 48 White House personnel tested positive for coronavirus during the outbreak. Many individuals involved initially tested negative through antigen testing, but later tested positive for the virus.
Why RT-PCR testing is better than rapid antigen testing
While no test gives a 100% accurate result, a review of COVID-19 test accuracy reported that RT-PCR tests had false negative rates as low as 2 percent. PCR testing is a more complex process, and involves converting the virus into viral DNA and observing the DNA for acute infection. Because RT-PCR testing detects the genetic material specific to the virus, the test can detect the virus even if you’re not showing symptoms.
How accurate is the empowerDX at-home COVID-19 test?
Our test is tied for the best sensitivity on the market and can detect the virus in smaller amounts than every other home COVID-19 test. This means you can know you’re infected earlier, even before you start showing symptoms. According to an FDA review in December 2020, our SARS-CoV-2 assay is tied for the highest sensitivity, with a limit of detection of 180 NAAT Detectable Units/mL) among 118 labs who submitted their results to the FDA SARS-CoV-2 Reference Panel.
Essentially, a test from empowerDX can detect less virus on a sample than every other test on the market. It’s sensitivity at its best. If the amount of virus collected on the nose swab was as low as 180 NDU/mL, the empowerDX test would be the only home-kit to offer a true positive. All other self-collected tests would show a false negative.
And false negatives are a major issue when it comes to COVID-19 testing. The highest LoD on the market right now misses a majority of infected patients, and false negatives can be as high as 70 percent. As the LoD increases, so does the likelihood that tests can miss infected patients. Emerging research suggests that each 10-fold increase in the LoD can increase the false negative rate by 13 percent – meaning that tests are missing an additional one in eight infected patients.
On other hand, a lower LoD means a test can detect the COVID-19 virus when there’s less of the virus in your body, which may result in earlier detection of a COVID-19 infection.
What can I do to stop the spread of COVID-19?
If you’re only relying only on rapid antigen testing to protect your family, friends, and communities from COVID-19, you’re putting those you care about at higher risk of being exposed to the virus. RT-PCR testing can help you reduce the risk of spreading the virus, especially if you’re asymptomatic or presymptomatic. Recent research from Harvard University suggests that frequent testing for COVID-19 can help reduce or eliminate the spread of the virus.
With RT-PCR testing, you can get peace of mind knowing that you’re getting the most sensitive at-home COVID-19 PCR test on the market (validated by the FDA on 12/7/20). Order your nasal PCR test from empowerDX today, and get results in just 48 hours.