When the doctor tells you that you will need to be tested for COVID-19 or if you personally decide to undergo a test, how do you choose between the Antigen Rapid Test (ART), Polymerase Chain Reaction (PCR) or serology test?
The array of available COVID-19 tests can be confusing to choose from, but the reason why there are multiple tests available is that they cater to the needs of different situations such as to diagnose an active COVID-19 infection or identify a previous infection.
Knowing the differences between each COVID-19 test can help you make a more profound choice in getting the right test done.
Primarily, there are two types of COVID-19 tests - diagnostic tests and antibody tests. Diagnostic tests require a nasal or throat swab, or saliva to identify an active infection of the
SARS-CoV-2 virus, the virus that causes COVID-19. Meanwhile, the latter examines a person’s blood for antibodies that may indicate a previous COVID-19 infection.1
You may know these tests better by its name, such as:
Learn more about the differences as well as the pros and cons for each COVID-19 test below.
Also known as a ‘rapid test’, as the name suggests, an ART is able to produce results in about 15 to 30 minutes.1
You are encouraged to stock up at least 2 sets of ART self-test kits³ so that you may use them whenever needed. This test is especially helpful to detect an infection quickly and is great for routine checks.
You may head to your doctor’s office for a test or if you are comfortable with conducting it yourself, you may purchase an ART self-test kit The Singapore government has released a guide known as the ABCDs of ART Self-testing³, which stands for:
A – Act if you are worried that you may have a COVID-19 infection by getting yourself tested.
B – Be informed by reading the manufacturer’s instructions properly.
C – Check yourself by ensuring that your hands are clean and the test is conducted according to the manufacturer’s instructions.
D – Dispose the ART self-test kit in the bag provided upon completion and throw it immediately.
Pros: An ART is a quick and pocket-friendly option that is conveniently available on shelves and online.
Cons: ART is a highly accurate test but if there are low levels of the virus in the sample, it might not detect an infection.5 Therefore, a PCR test may be required in some circumstances.1
The PCR test looks for the genetic material of the SARS-CoV-2 virus in the swab sample taken from your upper respiratory tract. Unlike ART, PCR tests can only be conducted by trained healthcare professionals and the specimen will be tested in a laboratory.6
Currently, the PCR test is the gold standard for diagnosing COVID-19 infections and is recommended to confirm a COVID-19 infection.2
The procedure for the PCR test involves swabbing the back of your nose and throat. It is important to stay calm during the procedure. To prepare yourself, perhaps listening to your favourite choice of music while waiting for your turn could help to ease your nerves.
You might feel a slight sting during the procedure but not to worry, it takes just a couple of seconds. As for your results, it takes about 24 hours turnaround time or more before you are notified.
Pros: It is more sensitive at detecting the SARS-CoV-2 virus4 in the specimen. Therefore, producing more accurate results than ART.5
Cons: This test requires the manpower of trained professionals.6 It is also more costly and takes a longer time to process the specimen.
You may wonder, what is the difference between the ART and PCR tests? While both tests are diagnostic tests and require a swab sample, the ART test will require a higher level of the SARS-CoV-2 virus to be present before showing a positive, whereas the PCR test will show a positive even if there is a small amount of SARS-CoV-2 virus in the swab sample.5
A serology test is a blood test that detects antibodies developed by the body as an immune response to a threat, such as a virus like SARS-CoV-2. This test should not be used to diagnose an active COVID-19 infection.1
The serology test is recommended only after you have experienced symptoms of COVID-19 for at least 14 days, as it can take a couple of days or weeks for antibodies to develop after an infection.1 If the test is conducted earlier, it may not produce accurate results.6
You will have to pay a visit to a healthcare facility to have a serology test done. A trained medical staff will take a blood sample (by drawing blood from your vein or a finger prick) and send it to a laboratory to have it tested. It can take a couple of days before you receive your test results.7
Pros: This test can show if a person was previously infected by COVID-19, even if the infection was months before the test was conducted.7
Cons: It is not able to diagnose an active COVID-19 infection.1, 6
At Roche, we understand the importance of delivering effective and reliable solutions to flatten the curve for COVID-19. As a leader in diagnostics testing, we are committed to delivering quality COVID-19 tests to effectively detect the SARS-CoV-2 virus. Our PCR, ART and serology tests cater to the needs of the healthcare system as well as the community.8
As you have discovered, each COVID-19 test does have its unique differences and advantages. The PCR test remains the most sensitive but there is no doubt that the ART and serology test are helpful in managing COVID-19 as well. Ultimately, testing for Covid-19 is the best way to identify and prevent the spread of the virus. It is also for your peace of mind if you are worried about a possible infection.