Why a SARs-CoV-2 qPCR Assay for Cannabis is Necessary

In the midst of the COVID-19 pandemic, 31 states declared some form of cannabis to be “essential.” However, it would be naive to think that means the industry is invulnerable to a COVID-related shutdown. If last summer’s vape scare taught us anything, it’s that politicians will pull the plug on the cannabis supply chain if it is believed to be a vector for COVID-19 transmission. 

So far, the SARs-CoV-2 virus has NOT been detected on cannabis, and it’s NOT believed to be a replicative host. However, it’s also not clear whether the lack of detection is partly because no one is looking. At least until now. 

In an effort to better assess the cannabis fomite risk, the Medicinal Genomics team developed a quantitative PCR assay for the SARs-CoV-2 virus that is optimized to operate with a hemp flower background matrix. We then inoculated Gamma irradiated SARs-CoV-2 virus into hemp flower and extracted and quantitated with qPCR across 7 days. As you can see the virus remained stable during the 7-day period. It’s important to note that this study was done with non-viable virus and shouldn’t be used to discern viability.   

Testing is Needed to Proactively Prevent Shutdown 

This assay arms cannabis testing labs with the tools they need to test cannabis material for the SARs-CoV-2 virus within the cannabis supply chain. This assay should in no way be construed to assume that cannabis patients are at risk or that access to medical cannabis should be curtailed. 

Although the results show cannabis may be a viable fomite for SARs-CoV-2, we do not believe it to be a replicative host. However, a proactive approach to testing for SARs-CoV-2 in the cannabis supply chain is the only way to test that hypothesis, and thus ensure patient safety and the financial survival of our industry. 

When you consider that over 90% of COVID-19 fatalities are from comorbid cases and many of those comorbidities intersect with conditions often found in cannabis patients (Cancer, COPD, Hypertension), we feel it prudent to investigate the risk. 

Furthermore, bat guano is serving as a rich source of coronavirus discovery, and it is also used as a fertilizer in some cannabis grows. In addition to this, we have cannabis trimmers and other employees testing positive for SARs-CoV-2 and human to plant transfer of virus to the supply chain may require more scrutiny. Any human contact in the dispensary from sniffing samples to handling them for consumer inspection is an exposure risk and should be limited to sacrificial show samples that are not sold to consumers.

In summary, we believe SARs-CoV-2 will be more rare than Aspergillus on cannabis, but the consequences of the rare event could be lethal for the industry. As a result, we have taken the first step in preemptive test design and validation of assays for detecting this in cannabis supply chains and look forward to working with many labs to further this field of work.

Please contact us if you are interested in testing for SARs-CoV-2 on cannabis.