A new study found that patients who recover from the coronavirus eventually produce antibodies to the virus, suggesting they may be capable of warding off reinfection.
Researchers in China tested the blood of 285 patients hospitalized with severe COVID-19 illness and found that all had developed antibodies within two to three weeks of their first symptoms.
Antibodies are blood proteins produced by the immune system to fight viruses and may prevent future infections.
The study, which was published in the Nature Medicine journal by researchers at Chongquin Medical University, “brings much-needed clarity, along with renewed enthusiasm” to efforts to develop and implement widescale antibody testing, National Institutes of Health Director Francis Collins wrote Thursday in a blog post.
“Although more follow-up work is needed to determine just how protective these antibodies are and for how long, these findings suggest that the immune systems of people who survive COVID-19 have been primed to recognize SARS-CoV-2 and possibly thwart a second infection,” he wrote, using the technical name for the specific coronavirus causing the disease.
Governors and some public health experts have suggested using antibody tests to help reopen the economy; employees who test positive for antibodies would be allowed to return to work.
But it is not known how protective the antibodies are or how long immunity lasts after infection.
The market has been flooded with antibody tests with mixed reliability. As a result, the Food and Drug Administration (FDA) now requires commercial manufacturers to submit data to the agency proving their tests are accurate.
The FDA, in an effort to get the tests to market quickly, previously allowed manufacturers to self-verify the accuracy of their tests, but some were found to be unreliable or inaccurate.