Evaluation of ∑-MM™ molecular medium for the SARS-CoV-2 RNA stability over 90 days under different temperature conditions

The collection and storage of clinical specimens are critical determinants of reliable and accurate diagnostic outcomes. Swabs are commonly utilized for specimen collection aimed at the detection and identification of microorganisms. In this study, the ∑-MM™ Molecular Medium (Medical Wire and Equipment), which rapidly inactivates microorganisms, including bacteria, mycobacteria, and viruses, was evaluated for its capacity to preserve the stability of SARS-CoV-2 for up to 90 days under various temperature conditions. A total of 42 newly collected SARS-CoV-2 positive samples were selected to evaluate the performance of the ∑-MM™. Aliquots were stored under different conditions: at 4°C for 7 days, at room temperature for 7 days, at -80°C for one month, at room temperature for one month, at -80°C for three months, and at room temperature for three months. Samples were subsequently tested for SARS-CoV-2 RNA by Real-Time PCR. No statistically significant differences were observed across all storage conditions, when compared to the baseline measurements. The ∑-MM™ effectively preserves SARS-CoV-2 for up to 90 days at ambient temperatures, without statistically significant changes in CT values compared to baseline. These results validate ∑-MM™ as a reliable transport medium that enables specimen storage and transport under ambient conditions without compromising diagnostic accuracy. Given the demonstrated stability, future studies will explore the performance of ∑-MM™ over extended storage durations.