Abstract
The occurrence of the COVID-19 second-wave outbreak in Europe has pushed laboratories performing molecular SARS-CoV-2 tests to increase their throughput and decrease the result rendering time. In this evaluation, we tested for the first time a new, extraction-free, protocol with the Allplex SARS-CoV-2 Assay RT-qPCR kit on a Nimbus platform. Ninety-one samples, of which 71 previously tested positive with RT-qPCR with extraction were immediately analyzed without extraction, using only a dilution and thermal shock protocol. The positive and negative percentage agreements were respectively 97.2% (95% confidence interval [CI]: 0.90–0.99) and 95.0% (95% CI: 0.76–0.99). The two false negatives observed were very weakly positive with the comparison method. Moderate variations in Ct of the targeted genes were observed (median ± 95% CI): E gene, +2.49 ± 0.44; N gene, +0.98 ± 0.54; RdRP/S genes, +2.64 ± 0.48. On the other hand, the number of tests performed within 24 h raised from 86.4% to 97.8%, the turn-around time decreased from 19:18 to 09:03 (p <.0001), and the number of tests that can be performed per day doubled since this technique was introduced routinely in our laboratory.
Original language | English |
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Pages (from-to) | 2538-2542 |
Number of pages | 5 |
Journal | Journal of medical virology |
Volume | 93 |
Issue number | 4 |
DOIs | |
Publication status | Published - Apr 2021 |
Keywords
- COVID-19
- extraction free
- RT-qPCR
- SARS-CoV-2