Previously, molecular Covid-19 tests have only been authorised by the FDA for use in people showing symptoms of the coronavirus. This changed on Friday when the agency updated its authorisation of LabCorp’s viral RNA Covid-19 test, originally issued in mid-March, to allow the diagnostic’s use to screen for active infections in asymptomatic patients. When used in this manner a sample pooling technique must be applied to enable faster processing, with up to five samples being mixed and tested. LabCorp says that if the pooled sample comes back positive, the individual positive sample or samples can be identified using “patterns detected by its robotic testing platform”, though it also states that this is not always possible. The authorisation is intended to help efforts to reopen schools and workplaces, but several diagnostics companies have warned that demand for testing in the US is outstripping supply, causing turnaround times to lengthen. LabCorp, it seems, is not one of them – yesterday the group said it had increased its testing capacity to 180,000 tests per day, and reduced the average turnaround time to 2-3 days from specimen pickup.
Note: "Other" includes two antigen tests, two home sampling kits and one IL-6 test.