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The common methods of sample collection for the detection of SARS-Cov2 are either pharyngeal or nasopharyngeal. Both these methods require specific swabs that are in short supply, and both methods are not easily self-administered. A nasal swab can also be used to collect samples and is relatively easy to self-administer, yet obtaining nasal specific swabs can now also be a challenge. In order to address these issues, our group has optimized a protocol for self-administered nasal collection using buccal swabs that are not currently in high demand. With this method, we have been able to collect human samples with reliable results in RNA extraction based on RNaseP, and can detect SARS-Cov2 in known positive cases of COVID-19.

PCR based tests, such as quantitative PCR (qPCR) are the gold standard to test for the novel coronavirus (SARS-Cov2). Many labs regularly use qPCR for their own specific projects. The ability to process samples and detect SARS-Cov2 is not very different from the methods these labs are already intimately familiar with. This protocol outlines the methods that our group is using to detect SARS-Cov2 RNA in human samples.

Assay sensitivity is an important part of any lab test, this becomes a more critical issue when dealing with matters involving public health. The potential of pre- or asymptomatic carriers, as well as convalescents which have not completely cleared the virus are a public health risk. PCR based tests, specifically quantitative PCR is the gold standard to test for the novel coronavirus (SARS-Cov2), however, it is limited by its detection capabilities, and the results are based off of an amplification curve, rather than a real number or concentration. The limit of detection with quantitative PCR could easily yield a false negative for contagious individuals. In comparison, droplet digital PCR (ddPCR) is estimated to be 500 times more sensitive than quantitative PCR, and results are displayed as an absolute number (copies/uL). In this method our group adapted from our usual studies related to Parkinson's disease, we have been able to confirm that ddPCR is more sensitive than quantitative PCR, detect SARS-Cov2 RNA-spiked into human samples, and detect SARS-Cov2 in known positive cases of COVID-19.

Viral RNA isolation kits used in PCR based tests for the novel coronavirus (SARS-Cov2) are in short supply. Our group sought to identify a method to isolate viral RNA without the use of a kit or other supplies in high demand by clinical labs. Using a TRIzol based RNA extraction, followed by a glycogen precipitation, we are able to isolate a sufficient quality and quantity of RNA for quantitative PCR, and/or droplet digital PCR. This method has been confirmed to work as well as a viral RNA isolation kit, shown to work with SARS-Cov2 RNA-spiked into human samples, and in detecting SARS-Cov2 in known positive cases of COVID-19.

In the United States, access to testing for the novel coronavirus (SARS-Cov2) is severely limited. Arguably, the PCR based tests are the most reliable when it comes to detecting the virus. Critical reagents for these tests, however, are in short supply. Our group has worked to identify and test alternative reagents and supplies that are not in high demand by clinical labs. We have adapted a more traditional approach to isolating RNA does not use a kit. RNA isolated can be used in traditional quantitative PCR or droplet digital PCR, which has been shown to be ~500 times more sensitive.