Why did Utah stop using some rapid COVID tests? High number of false negatives found

Utah health officials stopped using the GenBody brand of rapid antigen tests this week after an analysis found nearly two-thirds of test results came back with different results from the final PCR tests – most producing false negative results.

But the company behind the test is now speaking out in favor of its product, as the state health department begins a review of what went wrong.

In the statement to KSL.com, GenBody wrote that it reaffirms its “commitment to producing accurate and cost-effective rapid COVID-19 antigen tests” amid the Utah Department of Health’s decision to suspend testing. use of testing. The statement goes on to say that the company is working with Utah health officials to determine the cause of the results.

It’s something the South Korean company, with a California-based distributor, says doesn’t appear elsewhere among the “millions (of tests) administered in nearly every state.”

Does this mean that the tests in Utah were not managed or administered according to instructions? This is a possibility under study.

GenBody says “due diligence” on their end has not yet led them to believe there is a problem with the test. They add that the test has been “validated in several independently conducted clinical trials,” including one recently conducted at Emory University.

David Yoo, CEO and founder of GenBody America, added that the company has not completed its investigation and will continue to work with Utah health officials “to review the procedures used to administer the tests.”

“The Utah results were surprising, but we are working tirelessly and diligently with the help of the Utah Department of Health to understand what may have contributed to these discordant results,” he said. declared.

Many Utah Department of Health-sponsored testing sites began using GenBody tests late last year as another spike in COVID-19 cases emerged in the state. . It wasn’t until early last week that there were signs of trouble with the brand, state health officials said.

The state said one of the testing sites reported that there was a discrepancy between the site’s GenBody rapid results and the PCR tests of an individual tested by both methods during the same visit. This triggered a review of around 18,000 PCR and GenBody tests on the day, which found that only 38% of rapid tests matched PCR results. Of Utahns with clear signs of COVID-19 symptoms, only 41% tested positive. These numbers caused the sudden pause, which was announced on Sunday.

The GenBody test review, according to Utah Department of Health officialswill seek to determine whether they were ineffective due to a design flaw or whether it was the result of delivery malfunction or operator error at the end of the state-sponsored test sites.

Based on what the health department has said about it, a Utah testing expert — independent of both sides — told KSL-TV on Tuesday that he suspects issues with shipping or storage could cause erroneous results. Jeff Midgley, owner of the Utah Lab to You company, has spent 30 years in the healthcare industry and says all rapid tests are fragile, which is why it’s important users follow instructions. described by the test manufacturers.

In the case of GenBody, there is a strict temperature at which the tests must be maintained. The company received emergency use authorization from the US government last summer, when its COVID-19 tests entered the market.

The Food and Drug Administration has since released the company’s 19-page instruction manual in line. It states that all kits should be stored between 35.6 and 86 degrees Fahrenheit, and that all “test devices, reagents, samples, and/or controls” should be at approximately room temperature before testing. This is, according to the document, anywhere between 15 and 30 degrees Celsius – around 59 to 86 degrees Fahrenheit.

There are other instructions, such as the foil pouch containing the supplies should not be opened until the time of testing, all devices should be placed on a flat surface, and all specimens should be tested immediately.

“If improper procedures were used, it would invalidate all test results,” Yoo explained. “We are unequivocally committed to ensuring that every precaution is taken so that people who rely on these tests can have confidence in the accuracy of the results.”

Midgley explains that this is a common problem with testing. In some cases, the solution may appear cloudy if compromised by temperature. Many of the tests received by Lab To You come with a thermometer that will turn gold once the container has been exposed to extreme temperatures.

If they see gold, they know to throw the tests away because they are compromised.

“If they are stored in cold (or) very hot environments, it can make the test bad,” he said. “That doesn’t necessarily mean it was bad testing, but could it have been shipped incorrectly? Could it have been stored incorrectly? … All of this will create false positives or negatives, and that’s what we see here in Utah now.”

There are no set guidelines for how testing is handled at Utah testing sites, a spokesperson for the state health department told KSL.com. All test sites are urged to obtain testing guidelines “directly from the test manufacturer”. When asked if the health department conducts inspections of test sites, the health department official added that he does not have that kind of authority, other than reviewing test sites. procedures on its own sites.

It’s unclear if the Utah testing sites that received different results followed the guidelines outlined by GenBody. At the same time, it is possible that differences between rapid antigen tests and PCR tests led to some of the differences found by the health department.

Rapid antigen tests do not always produce the same results as PCR tests because antigen tests are intended to capture when someone has a high viral load more than trying to capture if they are infected, public health experts told NPR last month. PCR tests can even produce positive COVID-19 results for weeks, meaning someone could test negative for COVID-19 via an antigen test and be positive in a PCR test based on the differences tests.

All of these are possibilities for issues reported by the state health department, and they will all likely be looked at over the next few weeks in addition to the tests themselves.

Between the break in Utah of the GenBody tests and the Recent FDA Recall of SD Biosensor Rapid Tests On “reports that the test kits were illegally imported into the United States,” Midgley says he’s aware people might have concerns about rapid antigen testing.

However, he said people should always have confidence in rapid antigen tests and their results as long as they follow the instructions for each type of test correctly.

“That doesn’t mean all the rapid tests are done and done because they’re still here and still great tests,” he said. “(Keep them at) room temperature. Don’t leave them in your car – heat or cold will ruin these tests.”