Wondering whether you, like countless others, have had a coronavirus infection but didn’t realize it because you had no symptoms?

Now you can get a Quest Diagnostics test that checks for antibodies — a sign of immune response — to the virus, and you don’t even need an order from your doctor.

There’s a catch: If you are insured and you go through your doctor, you’ll pay nothing out of pocket. But if you request the same test on your own, Quest, a leading diagnostics company, will charge you $113, plus a $10.30 service fee.

That’s because of a gray area in the new federal law, the Families First Coronavirus Response Act. It requires diagnostic and antibody tests ordered by a health-care provider — including telemedicine providers — to be covered by health insurers without cost-sharing.

The law says nothing about direct-to-consumer sales, or whether the physician ordering the test can be employed by the testing company. Under Quest’s setup, the consumer requests and pays for the test online, a Quest physician orders the test after making sure it’s appropriate, then the consumer has a tube of blood drawn at one of Quest’s 2,200 patient service centers. The results take a day or two to come back, and a Quest physician can discuss the results via telemedicine.

“With the introduction of this test and service, Quest is making it easy for people to access quality testing for antibodies, with access to physician interpretation and steering into needed care,” Quest chief medical officer Jay Wohlgemuth said in a statement Tuesday.

A Quest spokesperson said the new service does not fall under the federal law because “it’s a different offering. It’s consumer-driven.”

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Asked about direct-to-consumer sales of coronavirus antibody tests, a U.S. Food and Drug Administration spokesperson said it is allowed as long as “the testing is still prescription-based, with collection done at a collection site by trained health-care providers, with testing done in a high-complexity lab.”

The U.S. Centers for Medicare and Medicaid and the Health and Human Services Department did not respond to The Inquirer’s questions about whether such tests are exempt from the cost provisions of the new federal law.

The value of testing for antibodies after an infection ends remains to be seen. Scores of companies are now marketing tests. Quest’s version has received emergency authorization from the FDA, but most have not. Many private and government entities around the world, including the U.S. Centers for Disease Control and Prevention, are rushing to test various groups.

Although accuracy has been a problem, the hope is that the technology can help define the scope of outbreaks, the rate of asymptomatic transmission, and identify people with immunity. In theory, they could safely go back to work without social distancing. However, as Quest’s news release warned, “we do not yet know whether the development of antibodies provides protection from reinfection, or how long such protection lasts.”

The FDA has explicitly said that antibody tests may not be used as the sole basis to diagnose or rule out COVID-19.

Diagnostic testing for the coronavirus continues to require molecular analysis of a nasal swab sample collected from a patient.

In announcing the “consumer-initiated” antibody test, Quest stressed that it is not for people with an active infection or symptoms, and they “may not visit Quest patient service centers, which are not equipped to collect respiratory specimens.”

LabCorp, another diagnostics company with patient service centers across the country, recently launched an antibody test but is so far sticking to the traditional “ask your provider” sales model. “There are no upfront out-of-pocket costs to people who receive an order for a test through a doctor or health care provider,” the company said in a news release.