A new study published by Public Health England (PHE) has successfully evaluated the novel viral transport media PrimeStore® MTM (Molecular Transport Medium) for effective SARS-CoV-2 inactivation [1].
Working safely with live SARS-CoV-2 samples requires the use of high-containment laboratories. However, SARS-CoV-2 material can be handled at a lower containment level after inactivation, allowing more laboratories to undertake testing and thereby increasing COVID-19 testing capacity.
The PHE study [1] evaluated numerous commercially available reagents and laboratory formulations commonly used for viral inactivation protocols by public health agencies and research laboratories globally. All the tested reagents were utilized during the COVID-19 pandemic for sample transportation and subsequent molecular processing. PHE assessed 23 commercial reagents designed for virus inactivation, clinical sample transportation, and nucleic acid extraction for their ability to inactivate SARS-CoV-2.
The study used TCID50 and blind passage techniques to test for any infectious virus still recoverable from all samples treated with the inactivation reagents. Notably, the study showed that PrimeStore® MTM was the only commercially available transport reagent from the many tested, from which no residual virus was detected by either TCID50 or the passaging of treated purified sample. This demonstrates the efficacy and safety of PrimeStore® MTM in inactivating live SARS-CoV-2 samples whilst maintaining the ability to detect the target viral RNA.
In addition to this successful PHE evaluation of its effectiveness at deactivating SARS-CoV-2, PrimeStore® MTM is also an FDA-cleared and CE-IVD-marked sample collection device. It is already well proven, with millions of tubes sold globally for the inactivation and transportation of many high-consequence pathogens. Therefore, this patented transport media, manufactured by EKF and confirmed by PHE to enable safe handling of clinical samples, can help to increase COVID-19 testing capacity.
Due to PrimeStore® MTM’s advantages over generic VTM and UTM (viral and universal transport media) products, EKF has recently won several significant tenders with commercial partners in healthcare, education, and industry to supply safe sample collection kits for COVID-19 testing programmes.
Among these commercial partners, EKF is now working with the University of Leicester for its student COVID-19 screening programme and the international molecular diagnostics group Yourgene Health to supply kits to their customer base, which includes public schools, universities, and corporations. Another partner is Source BioScience, which provides ISO:15189 laboratory testing services for the NHS and private healthcare.
Dr Sean Sales, Director of Genomic Services, Yourgene Health, explained how PrimeStore® MTM has helped them to streamline their workflow and reduce the turnaround time for getting COVID-19 test results out to patients: “Our primary reason for choosing the PrimeStore® MTM was for safety. The MTM inactivates the SARS-CoV-2 virus whilst stabilizing the RNA. This means that we can safely handle samples we receive that could potentially contain a hazard group 3 pathogen in a Class II MSC. This, in turn, helps our workflow as it removes the need to inactivate the samples before moving to the next step.”
Sales added: “The fact that there’s no need for cold chain in the delivery process also makes sample delivery easier and helps keep shipping costs down. We are investing in our laboratory testing facilities to run tens of thousands of samples a month, and sample stability and supply are key.”
PrimeStore® MTM removes the need for all cold chain logistics, including sample storage; RNA and DNA are perfectly preserved for downstream molecular processing for up to four weeks at room temperature. Furthermore, because samples are rapidly inactivated, the risk of infection is eliminated, meaning samples are ready for safe testing immediately upon arrival at a laboratory and without containment. In the case of COVID-19, this opens up options for more testing laboratories, making PrimeStore® MTM a key part of the testing supply chain, which can underpin the safe and rapid increase of testing capacity.
Commenting on the PHE evaluation study results, Rebekah Stibbs, Product Manager for PrimeStore® MTM at EKF Diagnostics, said, “We were very pleased to note that the PHE study concluded that not all inactivation media are equal. The PHE study showed that the infectious SARS-CoV-2 virus remained recoverable in treated samples after inactivation with most reagents tested. PrimeStore® MTM was the only commercially available CE-marked and FDA-cleared media with no residual virus detected.”
Stibbs added, “The PHE study, and the fact that PrimeStore® MTM is proven technology used since 2006 for the inactivation and transportation of many high-consequence pathogens, have given our commercial partners the confidence to employ it in their COVID-19 testing programs now. As we enter the start of a second phase of the COVID-19 pandemic, safe, low-cost, low-maintenance sample transportation is needed more than ever before. This is so that the four UK governments can reach their testing targets and the UK can transition back to a normal way of life as soon as possible.”
References:
- [1] Stephen R. Welch et al. (2020). Inactivation analysis of SARS-CoV-2 by specimen transport media, nucleic acid extraction reagents, detergents and fixatives. J. Clin. Microbiol. (In Press).
