We’ve heard a lot about COVID-19 antibody testing recently. There are a number of commercial products on the market claiming they can detect if someone has had the virus – but are they accurate and are test results useful?
According to Kamran Kadkhoda, Ph.D., Medical Director of Cleveland Clinic’s immunopathology lab, there are still many unknowns.
“Why would one need to know if they were infected in the past? Because the immediate conclusion would be so, therefore, I am immune to it, I am immune to reinfection, but the main problem is – we don’t really know if that’s really the case,” he says.
Antibodies are molecules produced by the immune system to fight off infection. Kadkhoda says we don’t have a lot of knowledge about the antibodies that appear during and after the course of COVID-19 because the infection is so new.
Antibody testing for the virus isn’t 100 percent accurate yet and we don’t know if antibodies will protect us from another COVID-19 infection, as this type of information is typically gathered during long-term vaccine studies.
However, Dr. Kadkhoda says the tests might help researchers performing surveillance and epidemiological studies when a test with greater than 99 percent specificity is used.
Antibody tests are being used to identify potential blood plasma donors, as well. Studies are taking place to see whether blood plasma from people who have recovered from COVID-19 might help treat those who are critically ill with the disease. However, only clinical trials will be able to determine if this is a safe and effective approach to treating the virus.
“Some of the centers already started screening donors to see if they have high or low-level antibody and then based on that they can use that plasma in the context of clinical trials,” says Dr. Kadkhoda.
Kadkhoda says the best thing we can do to protect ourselves and others from COVID-19 is social distancing, hand washing and adhering to existing guidelines issued by credible organizations, like the U. S. Centers for Disease Control and Prevention (CDC).