The COVID-19 Test isn't scary or intimidating. COMMUNITY ER can give you a Coronavirus test in a matter of minutes! Keep reading to find out more about how the test is performed.
Step 1: You'll be swabbed
Testing for the new coronavirus isn't all that different from testing for the flu. First, doctors need to collect a specimen -- a sample that will be checked for the virus.
Health experts think the coronavirus replicates in the respiratory tract, causing respiratory illness, so the US Centers for Disease Control and Prevention recommends that clinicians swab your throat, going through both your mouth and your nose. People with "wet" coughs may also be asked to cough up sputum, a mixture of saliva and mucous.
It's unlikely that other bodily fluids will be tested, said Dr. David Hooper, chief of the Infection Control Unit at Massachusetts General Hospital. Because the illness so far has been flu-like and concentrated in the lungs, "they're probably not routinely testing for other types of body materials, such as stool or urine or blood. Although that may change in the future."
Step 2: Your specimen will be sent to a qualified lab
Once Community ER has collected your sample and stored in a sterile tube or vial, it's sent to a lab that has access to a test kit.
In the FDA-authorized tests, specimens are first chilled and shipped with an ice pack to a qualified lab, ideally using overnight shipping.
Chilled specimens can only be stored for 72 hours, but dry ice can be used to preserve the sample if delays are expected. Waiting too long may allow the virus and its genetic material to degrade, however, which could lead to a false negative.
Step 3: Your sample will be tested
Once samples arrive at a lab, technicians use a procedure called RT-PCR, or reverse transcriptase polymerase chain reaction, to look for the coronavirus. A similar test is sometimes used to identify the flu, and it allows clinicians to see whether a certain genetic sequence is present in a specimen -- such as the throat swab or sputum sample collected earlier.
Just like how every species has unique DNA, every virus has a unique genetic code. This code, called the viral genome, provides the blueprint for the virus as it replicates. Essentially, the coronavirus test works by determining whether any given specimen contains the distinct coronavirus genome.
To do that, technicians first extract any genetic information from the throat swabs and sputum samples. The purified genetic material is then mixed with a set of ingredients, including some derived from the coronavirus itself, and the entire solution is placed into a testing machine.
If a patient's specimen contains coronavirus, then the virus's genetic material will be amplified, and the machine will return a positive result. The viral sample will then be sent to the CDC's own lab in Atlanta, where the positive result will be confirmed.
How long does the test take?
Once a sample arrives at a state lab, test results can be available in as little as 24 hours, according to the Massachusetts Department of Public Health. That's important, said Hooper, because patients can be kept in isolation while awaiting coronavirus test results.
"When only the CDC was doing [tests] in the US," he said, "we would wait three days, or four, to get a result, which is obviously problematic if you have a patient in the hospital."
Individual hospitals are also working to develop their own tests, Hooper said, which "hopefully can be validated by the FDA under their emergency use protocol, and that would add to our capacity and would shorten turnaround time even further, so that we could potentially get a result within a couple of hours."
Commercial laboratories like LabCorp estimate three to four days from pickup of the specimen to release of the test result.
On Friday, the US Department of Health and Human Services announced it will fund two laboratories developing a diagnostic test that can detect novel coronavirus in approximately one hour.