How does pooled testing work?
Rather than doing a coronavirus test on every specimen, take a sample of each and combine it with samples from other specimens. Then run a single test on the pooled sample. If the results are negative, undoubtedly, all of the original samples are negative. Therefore, a single test has done the work of five or 10, compared with testing each sample individually.
The caveat is that if the pooled test comes back positive, it’s then necessary to test each original specimen individually, which requires more time and more supplies. However, if a lab is testing samples that return negative at least 90% of the time, the lab comes out ahead using the pooled approach.
South Korea, and other countries, have tested at far higher rates by quickly ramping up tests in the same week that their first cases were confirmed. The result was far fewer deaths because they were able to identify sick people and isolate them so that they didn’t infect others. Without adequate testing, the U.S. was forced to implement shelter-in-place orders, assuming that if you don’t know who’s infected, you have to believe everyone is.