With the arrival of more lateral flow tests with FDA EUA (Food and Drug Administration Emergency Use Authorization) approval that can be performed outside of a lab becoming more available, any business, educational institution or other organization can look into implementing their own coronavirus testing program.
And they are – especially schools, colleges, and universities. With a critical stake in creating safe conditions for students and staff to resume in-person learning, they are driving the development of in-house sample collection, testing and reporting systems. Labs are still involved, providing the more reliable confirmation tests for suspected positive samples with these new testing procedures.
These systems are focused, not on full-blown PCR-based quantitative testing, but in quick, simple screening and identification of possible cases, which can be rapidly quarantined and tested further, significantly reducing the risk of spikes. These fast-result tests render results in a matter of 15 minutes. Some are reportedly 97.1 percent sensitive, meaning it correctly diagnoses those with the infection in 97.1 percent of cases, and 98.5 percent specific, meaning it’s correctly ruled out for those without it. Regardless, qualitative PCR testing can then be brought in as a follow-up to any initial positives, to validate results.
A key element in successful high-throughput screening programs is the use of sample pooling. Also called a “composite sample”, a pooled sample is a single sample comprised of samples from more than one person – usually 5-10. This allows for more individuals to be processed in a shorter time. If the pooled sample tests negative, then all the patients are deemed negative. Two samples are taken from each patient. One of them is pooled with others. If a pooled sample tests positive in the initial screening test, the other samples taken from each member of that group are tested to determine which individual samples are positive and which are not.
The most daunting aspect of instituting such programs is establishing the infrastructure. It calls for a comprehensive data management system and an integrated process flow from registration to sample collection, testing and reporting that minimizes or eliminates errors – all of which being easy to understand and use, quick to deploy and suited to ongoing operation indefinitely. That is no small task when you are dealing with thousands of students and staff, and multiple samples from each, taken multiple times. Keep in mind that the typical turnaround at present is anywhere from 4 to 14 days, with many labs simply overwhelmed by the workload.