WASHINGTON (AP) – Blood tests for coronavirus could play a key role in deciding whether millions of Americans can safely return to work and school. But public health officials warn that the current “Wild West” of unregulated testing is creating confusion that could ultimately slow the path to recovery.
More than 70 companies have pledged to sell so-called antibody tests in the past few weeks, according to US regulators. Governments around the world are hoping that rapid tests, which typically use a blood test on a test strip, may soon ease public restrictions by identifying people who have already had the virus and who have developed some immunity.
But key questions remain: how accurate are the tests, how much protection is needed, and how long will that protection last.
Blood tests are different from the nasal swab tests currently used to diagnose active COVID-19 infections. Instead, tests look for blood proteins called antibodies, which the body produces days or weeks after fighting an infection. The same approach is used for HIV, hepatitis, Lyme disease, lupus and many other diseases.
Due to the relative simplicity of the technology, the Food and Drug Administration has decided to forgo initial testing as part of its emergency response to the coronavirus outbreak.
Currently, the tests are most useful for researchers studying the way the virus has spread in the U.S. population. The government said on Friday that it had started testing 10,000 volunteers. The White House has not defined a broader plan for testing and how the results could be used.
With almost no FDA control over the tests, “This has really created a mess that will take some time to clean up,” said Eric Blank of the Association for Public Health Laboratories. “In the meantime, you have a lot of companies that market a lot of products and no one knows how good it is. “
Blank’s group members, who represent state and local lab officials, urged the FDA to reconsider its lax approach to testing. This approach essentially allows companies to get started as long as they notify the agency and include disclaimers. Companies are expected to state that their tests have not been approved by the FDA and cannot rule out if a person is currently infected.
Last week, FDA Commissioner Stephen Hahn said in a statement that the agency “will take appropriate action” against companies that make false allegations or sell inaccurate tests.
Dr. Allison Rakeman of the New York Public Health Laboratory says some local hospitals assume that the tests, which are listed on the FDA website, “have been checked, when they weren’t.” “
According to Rakeman, the danger of a faulty test is that people will mistakenly conclude that they are immune or that they are no longer spreading the virus.
“Then someone goes home and hugs their 90-year-old grandmother,” said Rakeman. “You don’t want to give someone a false sense of security. “
For most people, the new coronavirus causes mild or moderate symptoms, such as fever and cough, which go away within two to three weeks. For some, especially the elderly and people with existing health conditions, this can cause more serious illnesses, including pneumonia and death.
For many infections, antibody levels above a certain threshold indicate that the person’s immune system has successfully fought the virus and is probably protected from reinfection. For COVID-19, it is not yet clear what level of antibody immunizes patients or how long the immunity can last.
Adding to the confusion is the fact that legitimate companies and fraudulent operators seem to be selling the kits. The distinction between the two can be a challenge.
Officials in Laredo, Texas, reported this month that some 2,500 antibody tests scheduled for use at a local driving test site were likely fraud. City officials had ordered what they were told were “FDA approved COVID-19 rapid tests” at a local clinic. But when they checked the accuracy of the test, it fell far below the promised range, the city said in a statement.
Examples of US companies bypassing the rules appear online and in emails to hospitals.
Promotional emails sent to hospitals and reviewed by the Associated Press did not include the required disclaimers. Some kits sold on websites advertise themselves as “FDA approved” for home testing. The agency has yet to approve any COVID-19 home testing. Blood tests should be processed by a laboratory.
“If you see them on the Internet, don’t buy them until we can give you a reliable test for all Americans,” said Dr. Deborah Birx, coordinator of the White House Coronavirus task force, at a recent briefing.
20/20 BioResponse is one of dozens of American companies that sell the tests to hospitals, clinics and medical offices. The Rockville, Maryland-based company imports tests from a Chinese manufacturer, but CEO Jonathan Cohen says his company has independently confirmed its performance in 60 American patients. He estimates the company has shipped 10,000 tests and has had to limit orders due to demand.
He said that antibody tests are not a “panacea, but neither are they garbage.”
Cohen called them “a tool in the toolbox that will have value with other tests. “
The business test is saved to the FDA website and includes all of the required disclaimers.
To date, the FDA has authorized only one COVID-19 antibody test from North Carolina diagnostic company Cellex. The agency has used its emergency powers, which means that a formal review is still required.
The White House has also tried to moderate expectations for testing, while promising that millions will soon be available.
Dr. Brett Giroir, the federal health official overseeing testing in the United States, told reporters a week ago that the FDA and other agencies were working to confirm the accuracy of the antibody tests.
“We will be very careful to make sure that when we tell you that you are probably immune to the disease … the test really said it,” said Giroir.
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