Validation of Microchip RT-PCR COVID-19 Detection System

While meeting the pandemic demand of SARS-CoV-2 testing, clinical laboratories worldwide tend to adopt new test systems offering cost-effective and faster test outcomes. However, the reliability of SARS-CoV-2 test results has paramount importance in the management of such a health crisis. Therefore, this study sought to determine the accuracy of the test results from a novel duplex Microchip RT-PCR test system using patient saliva samples and nasal swabs stabilized in Viral Transport Medium (VTM) with reference threshold Cycle Values (Ct). The VTM used to stabilize these samples during transport was found to be inhibitory to the RT-PCR. Therefore, all the samples were subjected to spin column purification of total RNA to remove the influence of VTM. A total of 70 patient samples, including 24 positive- and 31 negative-saliva in VTM samples and 15 positive nasal swab samples, were tested. Results obtained from both the sample types were compared to their reference values and no false positive or false negatives were observed. From this data, accuracy, specificity, and sensitivity were determined to be 100% applying the corresponding formulae. The limit of detection with 95% confidence probability was determined to be 2.5 copies/μl in the original sample.