Abstract
Community-based healthcare clinics and hospital outreach services have the potential to expand coronavirus disease 2019 (COVID-19) diagnostics to rural areas. However, reduced specimen stability during extended transport, the absence of cold chain to centralized laboratories, and biosafety concerns surrounding specimen handling has limited this expansion. In the following study, we evaluated eNAT (Copan Italia, Brescia, Italy) as an alternative transport system to address the biosafety and stability challenges associated with expanding COVID-19 diagnostics to rural and remote regions. In this study, we demonstrated that high titer severe acute respiratory virus syndrome coronavirus 2 (SARS-CoV-2) lysate placed into eNAT medium cannot be propagated in cell culture, supporting viral inactivation. To account for off-site testing in these settings, we assessed the stability of contrived nasopharyngeal (NP) specimens stored for up to 14 days in various transport medium (eNAT, eSwab, viral transport media [VTM], saline and phosphate-buffered saline [PBS]) at 4°C, 22-25°C, and 35°C. Molecular detection of SARS-CoV-2 was unaffected by sample storage temperature over the 2 weeks when stored in eNAT or PBS (change in cycle threshold [ΔCT ] ≤ 1). In contrast, variable stability was observed across test conditions for other transport media. As eNAT can inactivate SARS-CoV-2, it may support COVID-19 diagnostics at the point-of-care (POC). Evaluation of compatibility of eNAT with Cepheid Xpert Xpress SARS-CoV-2 assay demonstrated equivalent diagnostic accuracy and sensitivity compared to VTM. Taken together, these findings suggest that the implementation of eNAT as a collection device has the potential to expand COVID-19 testing to areas with limited healthcare access.
