3 Types of COVID-19 Tests, and Which One Is the Most Accurate
Molecular test (aka RNA or PCR test)
These diagnostic tests are considered the most sensitive for detecting an active infection, and the results are highly accurate. You might take one if you or your doctor think you have COVID. You might also be asked to take this type of test if you need to prove to your employer or your college that you are not currently infected prior to returning to work or campus In most cases, a health care provider will collect mucus from your nose or throat using a specialized swab. (Some molecular tests now use saliva, which people may find more comfortable.)
Molecular tests are often called PCR tests, short for polymerase chain reaction, the lab technique used to detect the virus's genetic material, explains the US Food and Drug Administration (FDA).
Turnaround time varies from minutes to days or longer, depending on whether the sample is analyzed onsite or sent to an outside lab, explains the Mayo Clinic.
Antigen test (aka rapid test)
This type of diagnostic test is often called a "rapid test" because the turnaround time is much quicker than an RNA test. It's also cheaper to produce. As a result, antigen tests are being used to screen large numbers of people, like at airports, a recent article in the journal Nature points out.From a patient's point of view, antigen testing works in much the same way as molecular testing.
Your health care provider will swab the back of your nose or throat to collect a sample for testing. But instead of waiting days for your results, an antigen test can produce a result in an hour or less, says the FDA.
If you test positive, it's probably correct: Antigen tests are highly accurate.
The problem is, these tests are more likely to miss active infection. If you have COVID symptoms but test negative, your doctor may order a molecular test just to rule out a false negative.
Antibody test (aka serology test or blood test)
This test looks for antibodies to the coronavirus.
Antibodies are proteins your immune system produces to fight off a foreign invader, such as a virus. A COVID-19 antibody test cannot diagnose active coronavirus infection.
All it tells you is whether you've been infected at some point in the past, even if that occurred months ago. Antibodies do not become detectable until at least several days after an infection has started.
Horses for courses people, this is why they have different tests. When a health system is overwhelmed, when contact tracers get overwhelmed....then different, quicker tests may need to be used,
