(Reuters) – Abbott Laboratories’ antibody test for the new coronavirus is highly likely to correctly determine whether people have ever been infected with the fast-spreading virus, the company said, citing a U.S. study.

Researchers at the University of Washington School of Medicine found Abbott’s test had a specificity rate of 99.9% and a sensitivity rate of 100%, suggesting very few chances of incorrectly diagnosing a healthy person with the infection and no false negatives.

Antibody tests can tell whether a person has ever been infected and are considered crucial in efforts to get Americans back to work safely as the presence of antibodies to the virus indicate possible immunity to future infection.

Abbott’s test was launched last month under the U.S. Food and Drug Administration’s relaxed rules for some coronavirus tests, allowing their distribution before regulatory clearance. It has since received emergency use authorization from the FDA. (https://reut.rs/3bd0ziI)

Abbott has already shipped more than 10 million antibody tests to hospitals and labs.

Roche Holding AG has said its antibody test has a specificity rate of more than 99.8% and sensitivity rate of 100%, and expects to ramp-up production to make more than 100 million tests a month by the end of the year. (https://reut.rs/2L98CSP)

Roche’s test has also received emergency use authorization from the FDA.

(Reporting by Saumya Sibi Joseph in Bengaluru; Editing by Shinjini Ganguli)