Amid surging coronavirus cases, the top U.S. testing official on Thursday announced another scale-up in the country’s diagnostic efforts, touting the importance of tests that can run from start to finish outside the lab.
The government will allocate an additional $550 million to community-based testing programs across all 50 states, said Adm. Brett Giroir, the assistant secretary for health. The government will also put $300 million toward 60 million kits for federal distribution to nursing homes and other vulnerable communities.
Dr. Giroir projected that the country’s capacity for non-laboratory testing could more than double by June.
In a video livestream, Dr. Giroir held up three new at-home testing kits, designed by Ellume, Abbott and Lucira Health, that recently received emergency green lights from the Food and Drug Administration. All can deliver results in a matter of minutes after a quick nasal swab, though only Ellume’s product can be purchased without a prescription.
The Abbott and Ellume tests search for bits of coronavirus proteins called antigens. Lucira’s test, like most laboratory-based tests, hunts for genetic material.
Dr. Giroir, who will depart his position on Jan. 19 as part of the transition to the Biden administration, praised the tests as “sophisticated” but cautioned that none were yet in widespread use. Production ramp-ups are in progress, he noted, but might not alter the market for a few months.
Ellume’s test, for example, while it will be sold over the counter in a few weeks, will still be available in only very limited quantities.
Experts have repeatedly cautioned that rapid tests are not as accurate or consistent as tests that route people’s samples through a laboratory, where they are typically processed with a technique called polymerase chain reaction, or P.C.R.
Rapid tests, which can run from start to finish in a matter of minutes, may also falter more often when used on people without symptoms. Even so, they are often used — as a way to frequently screen some populations like nursing home residents and schoolchildren.
But rapid tests typically have cost and convenience on their side — benefits that Dr. Giroir repeatedly underscored in a call with reporters. He noted the slow and bumpy rollout of testing in the United States, where speedy tests results are still a relative rarity.
Dr. Giroir said it was “not yet obvious” whether widespread at-home testing would be successful.
Susan Butler-Wu, a clinical microbiologist at the University of Southern California’s Keck School of Medicine, said at-home testing might streamline the testing process. People who feel sick could test themselves and determine whether they need to isolate or seek treatment in a matter of minutes.
But outsourcing testing to the general public also carries risks.
Incorrect results, for example, could be tougher to catch, interpret and act on when people test themselves at home. False negatives might embolden people to mingle with others, hastening the spread of the virus, while false positives could unnecessarily keep people out of work or school.
And both types of errors could erode public trust in testing.
Dr. Butler-Wu also noted that rapid test results might not make it to the right care providers and to public health officials when collected at home.
If results aren’t properly reported, she said, “you’re flying blind — you don’t know the prevalence in your community.”