VTM Solutions: Lessons from a COVID-19 Study
VTM Solutions: Lessons from a COVID-19 Study

VTM Solutions: Lessons from a COVID-19 Study

Mantacc scientist working in laboratory

Mantacc sponsored a research team to evaluate their viral transport media (VTM) solution for SARS-CoV-2 testing. The goal was improving test reliability and sensitivity. But the study results told a different story.

Mantacc was one of four VTM products included in the investigation. The researchers tested two SARS-CoV-2 strains from real patient samples. They used cultures with known viral titers to systematically assess impacts on test kit sensitivity. Four rapid antigen test kits were evaluated as representatives of technology commonly applied for COVID-19 screening.

The experiments examined how different sample processing conditions affected the test kits’ ability to detect virus. Inactivation methods were analyzed first. Heat treatment at 56°C for 30 minutes significantly reduced detection sensitivity – by 2-to-8 fold for the kits. However, mild β-propiolactone chemical treatment did not substantially influence results. This shows SARS-CoV-2 molecular components are heat-labile but can withstand gentle inactivation protocols.

The scientists tested how VTM solutions impacted detection across a range of viral loads. High titer samples at 50x the kit thresholds showed no issues. However, at lower virus concentrations of 10x and 2.5x the detection limit, Mantacc’s VTM severely affected sensitivity. Another VTM solution also reduced detection at low titers. But two additional VTM mixtures had minimal effects at any level.

The researchers examined sample storage impacts. Viral stocks were held at various temperatures and time periods before testing. Freezing cycles were also assessed. Encouragingly, kit performance declined slightly but remained mostly within expected ranges even under challenging preservation conditions. This indicates SARS-CoV-2 antigen integrity persists reliably during storage and transport. Thus, optimizing VTM formulations presents the most significant opportunity for improving test outcomes.

The investigation systematically delineated key factors impacting COVID-19 antigen detection methods. The results wholly surprised Mantacc by revealing that their VTM solution critically compromises sensitivity instead of supporting accurate diagnosis. After thoughtful analysis, Mantacc realized their VTM solution needs substantial improvement before further use.

This study provides invaluable lessons on unintended impacts of clinical solutions. While Mantacc intended to enhance viral screening, their VTM clearly needs reformulation to prevent false negative test results. Problematic VTM products could critically undermine public health efforts against the pandemic by missing contagious individuals. However, the investigation methodology also charts a path forward.

Mantacc is going back to refine and optimize their VTM mixture before additional testing. Following the clinical trial model, systematic analysis of detection sensitivity will ensure the new solution performs reliably across viral titers. Additional evaluation in real-world settings will then demonstrate its effectiveness for SARS-CoV-2 screening. These efforts will build evidence that Mantacc’s redeveloped VTM enables accurate COVID-19 test interpretation, supporting safe patient care decisions.

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Zhou H, Wang C, Rao J, Chen L, Ma T, Liu D, Ren L, Xu S. The impact of sample processing on the rapid antigen detection test for SARS-CoV-2: Virus inactivation, VTM selection, and sample preservation. Biosaf Health. 2021 Oct;3(5):238-243. doi: 10.1016/j.bsheal.2021.09.001. Epub 2021 Sep 9. PMID: 34518817; PMCID: PMC8426133.

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