The U.S. Equal Employment Opportunity Commission (EEOC) said on Wednesday that businesses can’t require their employees to take the coronavirus antibody test because to do so would violate the Americans with Disabilities Act (ADA).

The new guidance comes after the federal agency had given employers the green light to test employees to see if they had the virus.

This latest move from the agency tasked with preventing workplace discrimination comes as the EEOC has been constantly updating documents surrounding the coronavirus and employers’ response to it.

The Law 360 website reported on the development:

The latest entry deals with antibody or serology tests, which determine whether a person was ever infected with COVID-19 — even if they were asymptomatic — and built up antibodies to the disease. Pointing to recent guidance by the Centers for Disease Control and Prevention (CDC) that says in part that antibody tests shouldn’t be used to determine if someone is immune to the virus or as a basis for decisions about allowing workers back on the job, the EEOC said that employers for now can’t mandate those tests before allowing people back to work.

“An antibody test constitutes a medical examination under the ADA,” the EEOC said. “In light of CDC’s interim guidelines that antibody test results ‘should not be used to make decisions about returning persons to the workplace,’ an antibody test at this time does not meet the ADA’s ‘job related and consistent with business necessity’ standard for medical examinations or inquiries for current employees.”

“Therefore, requiring antibody testing before allowing employees to re-enter the workplace is not allowed under the ADA,” the EEOC said.

According to the CDC, serologic tests also can be problematic for potential false positives and no firm evidence yet that having the antibody means that an individual is immune to the virus for some period of time.

“Serologic testing should not be used to determine immune status in individuals until the presence, durability, and duration of immunity is established,” the CDC said.

The EEOC noted that this guidance could be adjusted depending on further developments in the battle to tackle the virus.

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