Today, there is still no definitive outlook as to when the world can eradicate COVID-19 for good, which is why COVID-19 tests that includes antibody testing remains a relevant topic for discussion. Because of this, everybody must be cautious about who they are dealing with. Businesses have required employees to show them negative test results for COVID-19 to go back to work.
However, companies that require negative test results should also consider the type of testing done to get the results. For example, antibody testing for COVID-19 will determine if a person has developed antibodies against the SARS-CoV-2 virus. However, having antibodies does not mean that the person is already immune against COVID-19.
What is Antibody Testing?
Antibody testing, also known as serology testing, is a test that determines whether a person has developed antibodies against a virus. Antibodies are proteins created by blood plasma to bind to an antigen to make it inactive. The formation of antibodies is part of the body’s immune response system. Antibodies are created to bind only to the antigen that is currently infecting the body.
What does Antibody Test Results Show?
People infected with COVID-19 sometime in their past will most likely develop antibodies that will fight the SARS-CoV-2 virus. Therefore, these people will have positive antibody test results. The positive results will only show that they had been infected by COVID-19. However, there is still no solid evidence that positive antibody results will mean that the person is already immune to COVID-19.
What are the Limitations of Antibody Tests?
Antibody tests are effective in determining whether or not a person has been infected with COVID-19. However, a person should undergo antibody testing at the right timing. A person who COVID-19 has been infected may show negative antibody test results since his body is still developing the antibodies. It is therefore recommended that antibody testing must be done at least two weeks after COVID-19 symptoms occur.
Antibody tests are limited in their accuracy and may show false-positive or false-negative results. A false-positive result occurs when the test shows positive results even if SARS-CoV-2 antibodies are not present. A false negative result occurs when the test shows negative results even if SARS-CoV-2 antibodies are present. Therefore, the best way to diagnose a person for COVID-19 is to undergo a COVID-19 PCR test.
Why are Antibody tests important?
Antibody tests are not meant to be a diagnostic test for COVID-19 since antibodies may take 1 to 3 weeks to develop after being infected. Therefore, antibody testing is only used to determine if a person has a past infection of COVID-19. One benefit of antibody testing is to select people who have recovered successfully from COVID-19 to become plasma donors. The plasma of recovered patients, known as convalescent plasma, may help people with weakened immune systems to recover from COVID-19. Likewise, convalescent plasma may also lessen the severity of the symptoms and lessen the length of COVID-19.
People who tested positive for the COVID-19 antibody test can continue with their daily lives. However, they should continue wearing PPE since they could still get reinfected with COVID-19.