Keeping your nose out of it with saliva-based detection of SARS-CoV-2

Managing the Covid-19 pandemic requires widespread and frequent testing. There is considerable interest in the use of saliva as an alternative to nasopharyngeal samples for diagnosis of SARS-CoV-2 infection. Saliva does not require specialized personnel or materials for its collection and can be easily provided by the patient. We have developed a simple, fast, and sensitive saliva-based testing method that requires minimal sample treatment and simple equipment. After heat inactivation, RNA is quickly released and stabilized, followed by reverse transcription loop-mediated isothermal amplification (RT-LAMP) and detection of positives using a colorimetric or fluorescent readout. The test is 100% specific and 95% sensitive, with a limit of detection comparable to commercially available real-time RT-PCR-based diagnostics. The method has been implemented in a CLIA laboratory setting for workplace surveillance and reporting.