District residents are now eligible to receive free COVID-19 antibody tests, Mayor Muriel Bowser announced Monday.

Residents interested in getting the test, which detects whether a person has built up antibodies to the virus after being infected, can call 1-855-363-0333 to schedule an appointment, Bowser said at a press conference. D.C. officials said the department set up a testing site at Canal Park and are hoping to construct an additional screening location.

“This, of course, is not the test that tells you whether you currently have COVID-19, but whether you were previously exposed to COVID-19,” Bowser said. “The results of these tests will help D.C. Health learn more about the rates of exposure in the city.”

Bowser said the tests, also called serology screenings, will help D.C. Department of Health officials gather more accurate information about D.C.’s COVID-19 exposure rate.

She added that D.C. officials are increasing the number of fire stations that offer testing throughout the week from two to four. District officials have published a full list of testing sites.

LaQuandra Nesbitt, the director of the D.C. Department of Health, said some residents may be eligible to receive antibody testing through their health care provider without needing to visit a public location.

She said having antibodies to a virus can sometimes signify immunity, but officials still do not know if the results indicate immunity for COVID-19. Nesbitt said people who test positive for antibodies should continue to observe social distancing guidelines, wear face coverings in public and practice “good hand hygiene.”

“All of those things will still be relevant for anyone who does have the presence of antibodies,” she said.