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bioRxiv · 10.1101/2020.04.11.036855

Evaluation of heating and chemical protocols for inactivating SARS-CoV-2

Pastorino, B.·Touret, F.·Gilles, M.·de Lamballerie, X.·Charrel, R. N.
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Abstract

Clinical samples collected in COVID-19 patients are commonly manipulated in BSL-2 laboratories for diagnostic purpose. We used the French norm NF-EN-14476+A2 derived from the European standard EN-14885. To avoid the risk of exposure of laboratory workers, we showed that Triton-X100 must be added to guanidinium thiocyanate-lysis buffers to obtain a 6-log reduction of infectious virus. Although heating protocol consisting of 92{degrees}C-15min was more effective rather than 56{degrees}C-30min and 60{degrees}C-60min to achieve 6-log reduction, it is not amenable for molecular detection on respiratory specimens because of important decrease of detectable RNA copies in the treated sample vs untreated sample. The 56{degrees}C-30min and 60{degrees}C-60min should be used for inactivation of serum / plasma samples for serology because of the 5log10 reduction of infectivity and low viral loads in blood specimens.

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Pastorino, B., Touret, F., Gilles, M., de Lamballerie, X., Charrel, R. N.. 2020-04-11. Evaluation of heating and chemical protocols for inactivating SARS-CoV-2. https://doi.org/10.1101/2020.04.11.036855

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