Evaluation of transport media and specimen transport conditions for the detection of sars-cov-2 by use of real-time reverse transcription-PCR

Abstract

The global coronavirus (CoV) disease 2019 (COVID-19) pandemic has resulted in a worldwide shortage of viral transport media and raised questions about specimen stability. The objective of this study was to determine the stability of severe acute respiratory syndrome CoV 2 (SARS-CoV-2) RNA in specimen transport media under various storage conditions. Transport media tested included UTM, UTM-RT, ESwab, M4, and saline (0.9% NaCl). Specimen types tested included nasopharyngeal/ oropharyngeal swabs in the above-named transport media, bronchoalveolar lavage (BAL) fluid, and sputum. A high-titer SARS-CoV-2 remnant patient specimen was spiked into pooled SARS-CoV-2 RNA-negative specimen remnants for the various medium types. Aliquots of samples were stored at 18°C to 26°C, 2°C to 8°C, and 10°C to 30°C and then tested at time points up to 14 days. Specimens consistently yielded amplifiable RNA with mean cycle threshold differences of 3 over the various conditions assayed, thus supporting the use and transport of alternative collection media and specimen types under a variety of temperature storage conditions.