Pooled Testing for Expanding COVID-19 Mass Surveillance

Diagnostic testing to identify patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays a key role to control the coronavirus disease (COVID-19) pandemic. While several countries have implemented the use of diagnostic testing in a massive scale as a cornerstone for infection control and surveillance, other countries affected by the pandemic are hampered by its limited testing capacity. Pooled testing was first introduced in the 1940s and is now used for screening in blood banks. Testing is done by pooling multiple individual samples together. Only in the case of a positive pool test would individual samples of the pool be tested, thus substantially reducing the number of tests needed. Several studies regarding their use for SARS CoV-2 have been done in the United States, Israel, and Germany. Studies have shown that an individual positive sample can still be detected in pools of up to 32 samples, and possibly even 64 samples, provided that additional polymerase chain reaction (PCR) amplification cycles are conducted with a sensitivity of 96%. Simulation studies to determine optimal pool size and pooling techniques have also been conducted. Based on these studies, pooled testing is shown to be able to detect positive samples with sufficient accuracy and can easily be used with existing equipment and personnel for population-wide screening.