PT  - JOURNAL ARTICLE
AU  - Amandine Gamble
AU  - Robert J. Fischer
AU  - Dylan H. Morris
AU  - Kwe Claude Yinda
AU  - Vincent J. Munster
AU  - James O. Lloyd-Smith
TI  - Heat-treated virus inactivation rate depends strongly on treatment procedure
AID  - 10.1101/2020.08.10.242206
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.08.10.242206
4099  - http://biorxiv.org/content/early/2020/08/10/2020.08.10.242206.short
4100  - http://biorxiv.org/content/early/2020/08/10/2020.08.10.242206.full
AB  - Decontamination of objects and surfaces can limit transmission of infectious agents via fomites or biological samples. It is required for the safe re-use of potentially contaminated personal protective equipment and medical and laboratory equipment. Heat treatment is widely used for the inactivation of various infectious agents, notably viruses. We show that for liquid specimens (here suspension of SARS-CoV-2 in cell culture medium), virus inactivation rate under heat treatment at 70°C can vary by almost two orders of magnitude depending on the treatment procedure, from a half-life of 0.86 min (95% credible interval: [0.09, 1.77]) in closed vials in a heat block to 37.0 min ([12.65, 869.82]) in uncovered plates in a dry oven. These findings suggest a critical role of evaporation in virus inactivation using dry heat. Placing samples in open or uncovered containers may dramatically reduce the speed and efficacy of heat treatment for virus inactivation. Heating procedures must be carefully specified when reporting experimental studies to facilitate result interpretation and reproducibility, and carefully considered when designing decontamination guidelines.Competing Interest StatementThe authors have declared no competing interest.