MANY TEAMS ARE TRYING, BUT SO FAR NO ONE’S DEVELOPED ONE.
BY DAN ROBITZSKI

Around the world, research teams are trying to develop a blood test for the coronavirus pandemic that might ultimately replace the nasal swabs doctors use today.

The main improvement that blood testing would have over swabs, Wired reports, is that they’d be able to measure a patient’s immune response. So instead of being limited to showing whether someone’s been infected with COVID-19, a blood test would also be able to tell doctors if that patient now has built up the antibodies necessary to fight off COVID-19 infections in the future.

As the pandemic progresses, knowing whether people have become immune will be a crucial factor for enabling people to once again safely congregate. Blood tests will also give doctors and health officials a better idea of how various outbreaks are spreading. Nasal swabs can sometimes return a false negative if whoever administers it doesn’t happen to mop up a sample that contains the virus.

But there’s a key problem: thus far, no one has developed a precise-enough blood test. For instance, Wired reports that one promising test will come back positive if it detects SARS-CoV-2, the coronavirus that causes COVID-19 — but will also do so for six other unrelated coronaviruses, rendering the result moot.

“It is amazing how many serological assays are coming out of the woodwork,” Elitza Theel, the clinical microbiology director of the Mayo Clinic, told Wired. “As well as making sure that they don’t mistakenly test positive for other diseases, we’re also ensuring that they do actually recognize COVID-19.”

“One of the challenges and delays has been just getting the kits in because of the transportation bans,” Theel added. “There are not a lot of flights happening. We’re currently looking at one assay from the U.S., two from Europe and two from China. There’s a need for this, so once we identify one we think is suitable, we’ll begin offering the testing.”

What remains unclear is when these tests will finally be ready for deployment — and Theel exercised caution against believing anyone who’s already developed one just yet. But once they are, she says, they could serve as a crucial tool for figuring out when it’s safe to return to some semblance of normal life.