COVID-19 Pool Testing Is a Stopgap Measure To Track and Curb the Pandemic

It could quickly amplify coronavirus testing by tenfold.


America's capacity to test for COVID-19 infections has greatly improved, rising from less than 1,000 per day at the beginning of March to around 600,000 per day now, according to the COVID Tracking Project. But the current level of testing is far from enough. Different researchers estimate that we need anywhere from 2 million to 30 million tests a day to fully reopen the economy safely. The idea is that frequent, widespread testing would stop the spread of the disease by quickly identifying infected people, who would then voluntarily self-isolate; physicians and public health authorities could then monitor and test people who had come in contact with them.

The Washington Post reported in May that few laboratories were testing at their full expanded technical capacities. This was probably because many Americans had become somewhat complacent about the pandemic, as the early exponential rate of growth in both cases and deaths was flattened through the broad adoption of social distancing.

What a difference a month makes. Laboratories are now warning that the escalating number of diagnosed COVID-19 cases in such places as Texas, Arizona, and Florida will soon strain even their now-expanded testing capacities. To address this looming shortfall, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told The Washington Post last week that Trump administration officials are looking into the possibility of pool testing.

Under this approach, samples from 10 to 20 people are combined and the pool is tested using just one coronavirus assay. Only if the test comes back positive is each individual in the pool tested for the infection.

"If you look around the globe, the way people are doing a million tests or 10 million tests is they're doing pooling," Deborah Birx, the coordinator of the Trump administration's coronavirus response team, told an online conference of the American Society for Microbiology last week. "Pooling would give us the capacity to go from a half a million tests a day to potentially 5 million individuals tested per day."

An even better bet would be to let cheap at-home diagnostic tests be made widely available. But in the meantime, pooling is a reasonable stopgap measure.