SGV Tribune

Antibody coronavirus testing ramps up, but beware of frauds, LA County officials say

Experts say the blood testing won’t determine who has it, but will determine who has had it, who might get it and who’s built defenses against it. The information will be critical in coming out of lockdown and in containing the spread.

In tandem with an increasingly robust coronavirus testing network, the Los Angeles County Public Health Department and USC researchers are ramping up another form of testing — for antibodies.

Antibodies are the body’s crime fighters, binding to alien invaders in your blood. They attack antigens — like viruses — with the hope of destroying them.

The county has teamed up with USC’s Price School of Public Policy for a COVID-19 antibody study, which began over the weekend at six testing sites in the county.

Researchers tapped a random sample of 1,000 adults living within 10 miles of testing sites.  The idea, officials said, is to create a representative sample of the county’s adult population. A first batch of results will begin emerging by this weekend.

If researchers can measure a person’s COVID-19 antibodies via blood tests, they’ll learn how the body’s immune system is responding to the infection.  This could be pivotal in determining when stay-home orders might be eased — currently extended until at least May 15.

On a larger scale, researchers are aiming to have a vital tool to in:

  • Detecting current and past COVID-19 infections. For instance, maybe somebody has it, but doesn’t realize they have it, because somehow they’ve got antibodies that are dealing with it.
  • Understanding the spread of the virus in the county. Over a period of months, public health experts will be able to track the spread better — including gaining a better sense of demographic data that could ultimately help in containing it.
  • Assessing future hospital bed and ventilator needs. If they better know the body’s immune response, they’ll better understand who is the most vulnerable to becoming sick, and when.

“This gives us powerful information about how many people have already been infected in L.A. County, regardless if they ever have became sick or had a molecular test on whether they had the virus,” said Dr. Barbara Ferrer, the county’s public health director.

The action is part of a community surveillance strategy that has been launched across the county. Ferrer said she hopes to dig deeper into how the virus is spreading among:

  • Adults at large;
  • Healthcare workers;
  • Staff and residents at nursing homes and longer-term care facilities;
  • And underserved populations, where there’s concern that the pandemic is taking a disproportionate toll.

Ferrer stressed that the antibody tests — serology or serologic tests, as they are sometimes called — are not the same as the molecular tests that diagnose whether a person actually has the virus.  And she said there are no FDA-approved tests that do both.

Even if you have developed antibodies to the coronavirus, it doesn’t necessarily mean you are immune to it.

In March, the FDA issued a policy that allows developers of certain serological tests to begin to market and use them once they have determined their reliability. To date, the FDA has authorized only one Emergency Use Authorization for a serological test, which is intended for use by clinical laboratories.

Meanwhile, more than 70 test developers have notified the agency that they have serological tests available for use.

But the FDA has warned that some firms are falsely claiming that their tests are FDA approved or authorized, or falsely claim that they can diagnose COVID-19.

“Please don’t fall for the scams that are out there that offer you serologic tests in your home,” she said.

“There are no FDA-approved home tests for antibodies,” she added. “But I hope you all know, if it’s not an FDA-approved test, and if you are not working with a provider to determine whether you need to be tested, you should stay away from products that are marketed under false pretense.”