Abstract
Understanding the impact of environmental conditions on virus viability and transmission potential is crucial to anticipating epidemic dynamics and designing mitigation strategies. Ambient temperature and humidity are known to have strong effects on the environmental stability of viruses, but a general quantitative understanding of how temperature and humidity affect virus stability has remained elusive. We characterize the stability of SARS-CoV-2 on an inert surface at a variety of temperature and humidity conditions, and introduce a mechanistic model that enables accurate prediction of virus stability in unobserved conditions. We find that SARS-CoV-2 survives better at low temperatures and extreme relative humidities; median estimated virus half-life was more than 24 hours at 10 °C and 40 % RH, but approximately an hour and a half at 27 °C and 65 % RH. Moreover, our model predicts observations from other human coronaviruses and other studies of SARS-CoV-2, suggesting the existence of shared mechanisms that determine environmental stability across a number of enveloped viruses. Our results highlight scenarios of particular transmission risk and point to broad strategies for pandemic mitigation, while opening new frontiers for the mechanistic study of viral transmission.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
We now report results from a 3 parameter version of our mechanistic model; this version uses the same activation energy above and below the efflorescence relative humidity. We have also made revisions and additions to the text to clarify key points and discuss additional implications of the work. Our central findings have not changed.
