Though the potential is high for false positives and false negatives, some experts believe at-home COVID-19 testing still holds promise for slowing the spread of the coronavirus
Laboratory Corporation of America (LabCorp) is the first diagnostic test developer to receive approval from the US Food and Drug Administration (FDA) to market an at-home specimen collection kit for COVID-19. In an April 21 FDA news release, the federal agency announced it had “re-issued the emergency use authorization (EUA) for the Laboratory Corporation of America COVID-19 RT-PCR Test to permit testing of samples self-collected by patients at home using LabCorp’s Pixel by LabCorp COVID-19 Test home collection kit.”
The kit includes a nasal swab for specimen collection and a shipping package for returning the sample to a designated medical laboratory. Pixel is designed to work with LabCorp’s COVID-19 RT-PCR test, a real-time reverse transcription polymerase chain reaction (rRT-PCR) test that determines if an active SARS-CoV-2 coronavirus is present. The Pixel specimen-collection kit can be purchased for $119 on LabCorp’s website.
Presently, the Pixel kit is only available to healthcare workers and first responders who are symptomatic or who believe they may have been exposed to the virus. However, in a news release LabCorp stated that it “intends to make COVID-19 self-collection kits available to consumers in the coming weeks.”
Though purchasers have to pay for the kit themselves, a notice on LabCorp’s website states that the company “will work with you to get your purchase reimbursed by your health plan,” and that LabCorp is “actively working on a more streamlined solution, so you don’t have to pay up front.” LabCorp created a COVID-19 microsite where customers can receive future updates on the Pixel at-home test kit.
Though Finger-stick At-home Tests Prove Inaccurate, Optimism Remains
As COVID-19 wreaks havoc around the globe, in vitro diagnostic (IVD) developers, clinical laboratory companies, and healthcare professionals have scrambled to find an accurate, cost effective way to definitively test individuals for the coronavirus.
Complicating matters is the fact that many people are asymptomatic carriers who show no symptoms of the illness, but who can infect others.
Earlier this year, the UK government was optimistic that an at-home serological antibodies test would enable its citizens to collect their own blood specimens via finger sticks, and that the test would provide a way for individuals to test themselves for the coronavirus.
According to CNBC, the United Kingdom (UK) ordered millions of antibody tests, but after disappointing results, returned the kits and requested a refund.
The New York Times (NYT) reported that the British government paid $20 million upfront for two million untried antibody test kits from two Chinese companies: AllTest Biotech in Hangzhou and Wondfo Biotech in Guangzhou. Then, UK government officials announced the tests would be available to citizens within weeks, and Prime Minister Boris Johnson publicly declared the tests would be “simple as a pregnancy test.”
Neither of those predictions would come to pass. In April, British researchers announced that none of the coronavirus tests they had tried were accurate enough to be of any value.
“Sadly, the tests we have looked at to date have not performed well,” said Sir John Bell, Regius Professor of Medicine, University of Oxford, Medical Sciences Division, in a blog post titled, “Trouble in Testing Land.”
“We see many false negatives … and we also see false positives,” he wrote, adding that the UK “is now uniquely positioned to evaluate and find the optimal test for this disease, but no country has found a kit that is up to standard.” He also noted that locating such a test should be possible, but that it may take another month or more to find.
The Chinese companies defended their tests. In the Chinese newspaper Global Times, Wondfo stated its tests are “intended only as a supplement for patients who had already tested positive for the virus,” and on its website, AllTest stated its tests should “only [be] used by professionals,” not by patients at home, the New York Times reported.
Will At-home COVID-19 Testing Ever Work?
At-home testing kits for COVID-19 may seem like a great solution to the testing dilemma, but they could also prove to be problematic. “This may not be as good as it sounds,” Edo Paz, MD, a New York Presbyterian-trained cardiologist, Clinical Director at Heartbeat Health, and Vice President Medical, at K Health, a digital health company located in New York City, told CNET.
“Collecting a proper sample from the nose or mouth takes training and shipping delays of the specimen back to the lab could impact the quality of the sample,” he said, adding, “There could be a high false negative rate, leading people who are actually infected to believe they are not, potentially contributing to the crisis.”
Clinical pathologists have a unique understanding of the challenges that must be overcome for capillary blood to be of any use for testing, and of the potential for mishandling of specimens inherent in at-home test kits.
Nevertheless, with the SARS-CoV-2 coronavirus continuing to infect people around the world, the number and variety of tests will likely increase, which could create an upsurge in business for clinical laboratories and present new challenges for performing COVID-19 tests.