Many employers have heard of various workplaces testing for antibodies in regards to COVID-19. As businesses are wanting employees to feel confident in returning to the office, there are still various unanswered questions in regards to the testing. Read this blog post to learn more.

Many companies are considering offering their employees antibody (Ab) testing for SARS-CoV-2, the virus that causes COVID-19. While businesses want employees to be confident about returning to work, and the government wants better estimates of infection rates, there are still many questions about the value, reliability and usefulness of the testing.

The Basics of Antibody Testing

Ab testing uses a blood sample to look for antibodies the immune system develops to fight SARS-CoV-2. The test may show the presence of antibodies, an indicator of a likely past SARS-CoV-2 infection. Negative results indicate that a past infection is not likely. Neither result confirms whether the individual is currently infected (asymptomatic or otherwise), and Ab tests should not be used to diagnose whether someone is presently infected with COVID-19.

It typically takes 10-18 days following infection for the body to produce enough antibodies to be detected. A positive result does not indicate whether the detected antibodies can provide any protection or immunity against becoming infected again.

The U.S. Food and Drug Administration (FDA) has so far barred test producers from selling the tests to the public. Ab tests for SARS-CoV-2 must be administered by a federally approved health care provider or research group. For more information, see this guidance on the World Health Organization website, as well as this information from the FDA.

What Are Antibodies?

The presence of antibodies to any virus confirms past exposure to that virus or the receipt of a vaccine for it. The body remembers that exposure and will recognize the virus if exposed again. Antibodies take time to develop into their role as the body’s biological memory of past infections. Because many of us have not been exposed to this new coronavirus, our immune systems have no memory of it.

Those who may have antibodies for SARS-CoV-2 may not necessarily be able to fight off a second infection. To do that, the body needs sufficient numbers of antibodies, and they need to be effective. The degree to which people with coronavirus antibodies are protected from getting COVID-19 a second or third time is still unknown. Broad use of Ab tests and clinical follow-up will provide these answers. According to the U.S. Centers for Disease Control and Prevention, “we do not know yet if having antibodies to the virus that causes COVID-19 can protect someone from getting infected again or, if they do, how long this protection might last. Scientists are conducting research to answer those questions.”

If the antibodies are effective in causing immunity, we must also determine how long they might last in the body. Other coronavirus antibodies tend to last a few years. Those for the common cold can last only a few weeks or months. After the SARS coronavirus outbreak in 2003, one study found that only 9 percent of people had antibodies six years after getting sick.

Next Steps for Employers

Currently, there are many reasons why employers might hesitate to pursue Ab testing for employees. Ab tests only look backward, and most people will already know if they had COVID-19. Some physicians insist that test results offer little guidance on how or when to reopen workplaces, and organizations shouldn’t modify policies or procedures based on test results. They argue that safety procedures should remain the same regardless of Ab test results. Unfortunately, testing may make things worse, as some people who test positive for having antibodies may relax social distancing and sanitizing in the belief that they are now immune.

Knowing what to do with the test results is the primary dilemma. Encouraging blood draws and testing among employees may not be a compelling pursuit for companies until we know what to do with the results. Major questions remain:

  • Quantity. We don’t know the degree to which people infected by the coronavirus develop antibodies. Some may never develop antibodies. Figuring that out requires longer-term studies of who gets reinfected.
  • Effectiveness. We don’t know the degree to which the antibodies provide immunity and protection.
  • Consistency. We don’t know how consistently these antibodies provide protection from person to person.

If Ab testing in the workplace is used, it should be accompanied by a clear explanation of what the results might indicate about the employee’s past health and what they do not indicate about the employee’s present and future health status.

SOURCE: Musselman, K. (29 May 2020) “Antibody Testing for COVID-19 in the Workplace” (Web Blog Post). Retrieved from https://www.shrm.org/resourcesandtools/hr-topics/risk-management/pages/antibody-testing-for-covid-19-in-the-workplace-.aspx