Coronavirus Testing Used by the White House Could Miss Infections

A rapid coronavirus test used by the White House to screen its staff could miss infections up to 48 percent of the time, according to a study by researchers at N.Y.U. Langone Health.

In a statement, the company defended its product, saying, “ID Now is an important tool that delivers information where it’s needed most.” Abbott said that its reported rate of false negatives — or missed infections — was 0.02 percent and that the N.Y.U. study’s results were “not consistent with other studies of the test.”

“It’s unclear if the samples were tested correctly in this study,” the company said. “In communications with the users of the test, it is performing as expected.”

The authors of the N.Y.U. study said they evaluated the Abbott test because they were considering using it to test emergency department patients who were suspected of having the virus.

The N.Y.U. researchers tested how the machine fared when the dry swabs were used. They took two samples each from 101 emergency department patients at N.Y.U. Langone Tisch Hospital who were suspected of having Covid-19. One sample used the longer nasopharyngeal swab and was stored in liquid. The second sample used dry nasal swabs. Each specimen was tested on both the Abbott ID Now and another machine, the Cepheid GeneXpert, which takes 45 minutes to yield a result and which has been validated by N.Y.U. as acceptably accurate.

The researchers found that the Cepheid machine identified 31 of the 101 patients as positive for the virus. But even when the dry nasal swabs were used, the Abbott ID Now identified only 16 people as positive. In other words, 15 patients had the virus, but the Abbott ID Now test said they were negative.

Using the dry nasal swab yielded less accurate results than when the researchers used a nasopharyngeal swab that had been stored in liquid. When those types of nasopharyngeal swabs were used, the Abbott missed infections one-third of the time, the researchers said.

The White House did not respond to questions about which types of swabs it uses.

The N.Y.U. researchers said that because the Abbott ID Now machine missed so many infections — including in patients who had to be admitted to the hospital — the technology is “unacceptable in our clinical setting.”

The researchers said their study was limited by the small sample size, as well as the one to two hours it took to transport the samples. Although that is within the manufacturer’s recommendation of two hours, the researchers note that the test is intended to be used where the patients are, not in a laboratory.

Reporting contributed by Jeremy White.

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