With the recent talks about covid-19 testing in the media, people cannot help but wonder what types of tests are there and how they differ. One type of testing that has caught the attention of many in the healthcare system is the antibody testing for covid-19. Also known as serology testing, antibody testing for covid-19 is used to determine if someone had a recent or prior covid-19 infection and detect any antibodies against the virus. That differs from the covid-19 diagnostic test that determines if someone has an active infection of the virus.
Why is antibody testing necessary?
As antibody testing is currently conducted on people who have recovered fully from a covid-19 infection. What happens is, healthcare personnel takes a blood sample from the patient by a finger prick. Then they test the sample to determine if the patient’s body has developed antibodies or immunity against the SARS-CoV-2 virus. This specific test detects antibodies or proteins made by the body in response to the virus infection.
If the antibody test turns positive, that indicates that the person has been infected with the SARS-CoV-2 in the past. But it does not mean they are currently infected. It may also suggest that the person has some form of immunity against the virus. However, there is still uncertainty whether having antibodies against the covid-19 virus means whether you are protected against reinfection. Another unknown case is the level of immunity and how long the immunity lasts, but ongoing research is more likely to reveal some of these things. The center for Disease Control and Prevention says that there is no enough information if someone is protected from reinfection again even if they have antibodies against the virus. There have been rare cases of confirmed and suspected reinfection, although rare.
Are there circumstances that affect antibody testing?
Yes, some circumstances affect the accuracy of antibody testing against covid-19. If someone gets the test in the earlier stage of the infection, the body is still building up immunity against the virus. Therefore the test will not detect any antibodies present. As such, antibody testing for covid-19 is recommended at least after 14days from the end of the symptoms. Again, the FDA has authorized only specific rapid covid-19 testing kits for antibodies so, people should beware of tests with questionable accuracy in the market.
How beneficial is antibody testing for covid-19?
Antibody testing for covid-19 is vital for determining if someone is developing immunity against the SARS-CoV-2 virus. People who have recovered from the virus and developed antibodies may be eligible to donate a part of their blood or plasma to help others with severe symptoms and boost their body’s ability to fight off the virus.
The results of antibody testing for covid-19 show how many people had covid-19, including those who did not have any symptoms. That is valuable in determining who might have immunity, to what extent, and how long it lasts. But, antibody test results should not be used to group people. Even if someone tests positive for antibodies against the SARS-CoV-2, they should still observe the covid-19 prevention measures.
Healthcare professionals who use the antibody tests for covid-19 should first understand how the tests work and how to interpret the results accurately.