COVID-19 tests can spot variants, lab companies insist

As public health officials warn that the new COVID-19 variant originating in the U.K. could become dominant across the U.S. by March, the nation's largest testing companies and laboratories say their coronavirus tests are prepared to accurately identify new virus strains as they emerge.

Quest Diagnostics and LabCorp., two of the biggest test processing labs in the U.S., say they haven't reported any changes to the accuracy of their testing data with false negatives from the new U.K. coronavirus variant.

Abbott, a U.S. medical device and health care company that produced rapid tests purchased in large numbers by the federal government, said its BinaxNOW tests are still working as promised.

"We've continued to track these new variants as they emerge," Dr. Mary Rodgers, principal scientist and head of infectious disease research at Abbott, told ABC News. "We've been bringing in samples to confirm our prediction based on the sequences, which indicate that there's no cause for concern for any of our Abbott tests."

The insistence by testing companies that their products are still working as hoped comes amid reports that the virus has mutated in countries where it spread widely. Three variants originating in the U.K., South Africa and Brazil have been documented in the U.S. and raised concerns that as the virus continues to mutate, that the nation's current arsenal of tests to detect the virus might become less effective.

In January, the U.S. Food and Drug Administration sent a notice to health care providers warning that the potential of future strains impacting testing accuracy is still possible. The letter said that variants could lead to false negatives in PCR tests and that tests designed to "detect multiple SARS-CoV-2 genetic targets are less susceptible."

Public health experts argue that such concerns from the federal government are legitimate and should compel testing companies to continue evaluating whether their tests are able to detect variants that are not yet on their radar.

In a statement on the new coronavirus strains, Abbott also said, "it is highly likely that future COVID-19 strains will remain detectable because we design our tests to be robust, knowing that virus mutations will naturally occur over time."

The type of test seems to matter when it comes to the variants. While medical experts agree that many viral tests are currently able to detect the new coronavirus variants, antibody tests are not. Viral tests determine if a person is currently infected with the virus, whereas antibody tests can suggest whether a person was previously infected.

"The antibody tests, at this stage, certainly are not able to determine or distinguish variation in Sars-cov-2 strains," said Dr. Jessica Justman, an associate professor of medicine in epidemiology at Columbia Mailman School of Public Health. "So, you can't get an antibody test and say 'I have an antibody to the new variant.' We just don't have that kind of test yet."

The steady spread of several new coronavirus strains worldwide has kept even Biden administration officials on high alert in terms of the federal government's approach to the pandemic. One concern is that as the virus mutates, it grows more transmissible and potentially more deadly. Preventing new aggressive strains from spreading is a priority, U.S. officials say, although the public health system hasn't been able to keep up.

"By the time someone has symptoms, gets a test as a positive result, and we get the sequence, our opportunity for doing real case control and contact tracing is largely gone," said Centers for Disease Control Director Dr. Rochelle Walensky at a White House COVID-19 briefing last month. "I believe that we should be treating every case as if it's a variant during this pandemic right now."

The Biden administration announced a $230 million-dollar deal with Ellume, an Australian digital diagnostics company, to provide 8.5 million over the counter at-home tests. Ellume plans to produce 100,000 testing kits per month through July and ramp up to 19 million a month by the end of the year.

The Ellume tests do not require lab samples and are described as being similar to how at-home pregnancy tests work. But even those tests will now be under scrutiny to determine whether they can detect viral variants, among other issues.

"Once these things go out into the real world, there's always potential for errors," said Dr. Wilbur Lam, an associate professor in the Department of Pediatrics at Emory University. "Health care policymakers will have to take all those things into account, and whether a confirmatory test is needed, that is likely going to be one of the use-case scenarios."