Efficient inactivation of SARS-CoV-2 by WHO-recommended hand rub formulations and alcohols

Annika Kratzel; Daniel Todt; Philip V’kovski; Silvio Steiner; Mitra L. Gultom; Tran Thi Nhu Thao; Nadine Ebert; Melle Holwerda; Jörg Steinmann; Daniela Niemeyer; Ronald Dijkman; Günter Kampf; Christian Drosten; Eike Steinmann; Volker Thiel; Stephanie Pfaender

Hand Hygiene in Health Care' suggests two alcohol-based formulations for hand 9 sanitization to reduce pathogen infectivity and spreading. These recommendations are 10 based on fast-acting and broad-spectrum of microbicidal activity, as well as easy 11 accessibility and safety 3 . We have previously shown that WHO formulation I and II 12 were able to inactivate the closely related SARS-CoV and MERS-CoV 6 Results 20 SARS-CoV-2 was highly susceptible to the WHO formulations (Fig. 1) . WHO 21 formulation I, based on 85 % ethanol, efficiently inactivated the virus with reduction 22 factors (RFs) of ï‚£ 5.9 and concentrations between 40 % -80 % (Fig. 1A) . Subsequent 23 regression analysis revealed similar inactivation profiles compared to SARS-CoV, 24 . CC-BY-NC-ND 4.0 International license author/funder. It is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.10.986711 doi: bioRxiv preprint 1 pathogenic human CoVs (Fig. 1A) . WHO formulation II, which is based on 75 % 2 isopropanol, demonstrated a better virucidal effect at low concentrations, with 3 complete viral inactivation and RFs of ï‚£ 5 at a minimal concentration of 30 % (Fig. 4 1B) . The regression analysis showed an inactivation profile of SARS-CoV-2, which 5 was in between SARS-CoV, BCoV and MERS-CoV (Fig. 1B) . 6