Coronavirus Testing: False Negatives Could Undermine COVID-19 Mitigation Efforts

Health experts say nearly one in three coronavirus tests may be giving false negative results, meaning people who have been told they don’t have the disease may be spreading it unwittingly. The Wall Journal reported the tests were developed with minimal regulatory oversight in the rush to make up for lost time as the pandemic began ravaging the country.

As the number of infections worldwide approached 1 million and deaths topped 50,000, the U.S. reported more than 226,000 confirmed cases with more than 5,300 deaths.

“A false negative is problematic because it tells the patient they don’t have the virus,” Dr. Craig Deligdish, an oncologist in Melbourne, Florida, told the Journal.

Health officials have said testing is key in determining how many people have contracted the virus, how it has spread and whether the pandemic can be stemmed. Models indicate if social-distancing guidelines are successful, the likely death toll could range as high as 200,000 -- if not successful, 10 times that figure. Inaccurate testing undermines the effort because infected people can continue spreading the disease.

Mike Lozano of Envision Healthcare Corp. told the Journal the current lab tests appear to have lower sensitivity than similar tests, finding only 70% of cases.

The Food and Drug Administration suspended rules requiring companies to submit tests for verification before deployment because of critics who said the process would deter companies from moving quickly. Instead, the FDA told companies to start testing and submit their internal studies later.

“Every action the FDA has taken during this public health emergency to address the COVID-19 pandemic has balanced the urgent need to make diagnostic tests available with providing a level of oversight that ensures accurate tests are being deployed,” the FDA said earlier this week.

The FDA has been working with more than 230 test developers and authorized 20 to begin testing while 110 laboratories are using their own tests.

Doctors told the Journal, however, patients who initially tested negative would return with worsened symptoms, and once admitted to hospitals, test positive. A spokesman for Labcorp said the false negatives could be the result of the way a specimen is collected and transported, and how soon after developing symptoms an individual was tested.