Laboratory-Developed Test for SARS-CoV-2 Using Saliva Samples at the University of California, Riverside

Hai, R.; Collin, M.; Tsau, S.; Raygoza, D.; Morrison, J.; Carrillo, A. J.; Collier, L. A.; Bayubay, W.; Han, K.; Kaloshian, I.; Borkovich, K. A.

Here we describe a relatively quick, simple, economical and accurate laboratory developed test (LDT) for detection of SARS-CoV-2 in heated and diluted saliva samples without RNA extraction. Our protocol is a variation of the University of Illinois Urbana-Champaign SHIELD LDT. Differences include chilling of the samples during dilution and using a reduced volume for the qRT-PCR reactions. The level of detection for our LDT is 3125 copies/ml, which compares favorably with other saliva-based tests. Initial validation studies with a limited number of patient samples have demonstrated excellent agreement between results using our LDT and those obtained from external laboratories. The cost of consumables for our test is under $8 and a throughput of 1000 tests/day can be achieved with 3-4 personnel.