Detroit officials defend rapid testing kits used for COVID-19

Christine Ferretti
The Detroit News

Detroit — The city's top leadership is maintaining confidence in the rapid COVID-19 testing kits used to screen thousands of city public safety workers and bus drivers amid new research questioning the reliability. 

Detroit Mayor Mike Duggan said Friday the city has used 15-minute testing from Illinois-based Abbott Laboratories to screen more than 8,000 individuals, over half of which have been front-line city workers including the majority of Detroit's 2,500-member police force.

Detroit Mayor Mike Duggan, along with Detroit Chief Public Health Officer Denis Fair and Detroit City Council President Brenda Jones, who tested positive for COVID-19 and has since recovered, speak on Detroiters and the coronavirus at a press conference at Shed 5 in Eastern Market in Detroit, Michigan on April 17, 2020.

"Our experience has been that the Abbott tests are catching the sick people and that they are not having any significant false-negative rates," Duggan told reporters during a Friday news briefing. "We're entirely confident."

Duggan's comments come after the Food and Drug Administration said late Thursday it was investigating preliminary data suggesting that rapid tests can miss COVID-19 cases.

The tests — used daily at hospitals, clinics and the White House to test President Donald Trump and his cabinet — are relied on heavily in Detroit for clearing first responders, vulnerable seniors and other essential city staff.

The FDA's review comes after New York University researchers reported results that suggested Abbott's test can miss up to half of the infections caught by a rival test. The findings were based on about 100 patients and haven't been peer-reviewed. 

The research concluded the test, run on the company's portable ID NOW system, missed one-third of the infections caught by the rival test, Cepheid, when swabs were stored in liquid used to transport laboratory samples. When the samples were kept dry, the test missed 48%, the study found. 

Detroit Police Chief James Craig added Friday that the city's police department alone "says it all." As of Friday, the department has 23 members positive for the virus and 59 members are in quarantine. At one point, more than 1,500 police employees were under quarantine, Craig noted. 

"We have seen a drastic decline," he said. "We've literally tested the entire department. In terms of confidence level, they are extremely confident."

A lab technician dips a sample into the Abbott Laboratories ID Now testing machine at the Detroit Health Center in Detroit. Federal health officials are warning about potential accuracy problems with the rapid test for COVID-19 used at thousands of hospitals, clinics and testing sites across the U.S., including the White House.

Abbott defended its ID NOW testing in a Thursday press release, saying it is "helping to reduce the risk of infection" by "detecting more positive results than would otherwise be found."

The company said studies are being conducted on the test "in ways that it was not designed to be used" and that the NYU results "are not consistent with other studies."

"While we've seen a few studies with sensitivity performance percentages in the 80s, we've also seen other studies with sensitivity at or above 90%, and one as high as 94%," Abbott officials noted. 

Duggan has rejected other assessments of Abbott technology, saying studies that have been critical weren't looking at processing the kits the way they are handled in Detroit. 

The company added that it's clarifying product information to better guide health care providers and reinforcing proper sample collection and handling. 

The FDA first cleared Abbott's test in late March under emergency powers used to quickly accelerate the review of tests and treatments during a public health crisis.

Trump briefly weighed in Friday on worries over the effectiveness of Abbott, calling it a "great" and "very quick" test.

"If you're testing positive or negative, it can always be double-checked," he said. 

White House Press Secretary Kayleigh McEnany, during a separate Friday briefing, said FDA head Stephen Hahn “continues to recommend the test" and Secretary of Health and Human Services Alex Azar “has confidence" in Abbott, “otherwise it wouldn’t be on the market.”

“That being said, they take any indication of false negatives very seriously,” she added. 

Azar believed there was “user error” in some of the studies, McEnany said, “meaning that the time transporting them might have affected the accuracy of the test.”

“To that end, what the FDA has said is that any negative test results that is not consistent with a patient’s clinical signs … you should consider getting a second test,” she said. 

The Michigan Department of Health and Human Services said Friday that there are "some concerns" regarding the study methodology and sample types used in some recent reports.

"While we agree that rapid tests have lower sensitivity and specificity as a whole than traditional tests, it should be noted that all tests have some problems," Bob Wheaton, a spokesman for MDHHS, wrote in an email.

"When used in the correct context with appropriate educational material being returned to a patient regarding risk, follow-up and potential future tests, the Abbott system is a good tool in our toolbox to confront testing challenges and long-term needs in the state."

The state has performed side-by-side comparison testing using both rapid and standard COVID-19 tests across samples from several geographic areas of the state. Of 82 patients to receive both an Abbott ID Now dry swab test and traditional test, 81 were provided the same result, Wheaton said. 

Detroit was among the first city in the country to deploy the rapid testing kits and machines to quickly screen Detroit's firefighters, police officers, bus drivers and other front-line workers. 

Duggan has since expanded use of the Abbott technology for seniors and staff members in city nursing homes, a vulnerable group hard-hit by the virus. The kits also are being used to screen workers of essential Detroit businesses as a slow return-to-work here begins. 

Detroit officials last week expressed confidence in the reliability of the Abbott technology, citing an independent analysis conducted by Detroit's health department.

For the study, a sample of 50 patients who tested negative for the virus with 15-minute tests from Abbott showed the tests were 98% accurate. 

"We did our own test and more than that, we now have experience with 8,000 people we've tested, more than 4,000 are our own employees," said Duggan, noting Friday that if the tests weren't accurately detecting cases of the virus Detroit would have known as more workers began to return. 

"I understand that the intensity over Abbott has to do with Washington politics. We are looking at the science in every single testing methodology. None of them is perfect," he said.

Abbott has said it distributed 1.8 million tests to health care facilities in all 50 states. The FDA said the test can still be used and correctly identify many positive cases.

Associated Press contributed.