Massive and rapid COVID-19 testing is feasible by extraction-free SARS-CoV-2 RT-qPCR

Ioanna Smyrlaki; Martin Ekman; Martin Vondracek; Natali Papanicoloau; Antonio Lentini; Johan Aarum; Shaman Muradrasoli; Jan Albert; Björn Högberg; Björn Reinius

The copyright holder for this preprint (which was not peer-reviewed) is . https://doi.org/10.1101/2020.04.17.20067348 doi: medRxiv preprint via the chin as far back in the throat as possible and scrape for 10-20s, then rinse the swab in the provided buffer for 10-15s. Instructions were also given to take a second wooden swab and introduce into the nose and scrape for 10-20s in each nostril, followed by a 10-15s rinse in the same buffer tube as the throat swab. The buffer in the swab test was 100mM PBS pH 7,4. Further instructions were to leave a saliva sample at the same time by spitting 3-4 times in a small jar during a 5-10min period. The samples were picked up and transported to a laboratory for testing typically within 1-10hrs after the sampling. Samples were stored at +4°C and RNA was extracted within 24h and tested using RT-qPCR. For the current study, the samples were deidentified aliquot of these same samples that had been subsequently frozen at -20°C for approximately 7 days, thawed and kept at room temperature ~2hrs, before performing the direct lysis experiments described herein.