SARS-CoV-2 Survival in Relation to Temperature and Humidity and Potential for Seasonality

SARS-CoV-2 Survival in Relation to Temperature and Humidity and Potential for Seasonality. Spencer EA, Heneghan C, Jefferson T.

Published on June 8, 2020

Reference National Academies of Sciences, Engineering, and Medicine 2020 Rapid Expert Consultation on SARS-CoV-2 Survival in Relation to Temperature and Humidity and Potential for Seasonality for the COVID-19 Pandemic (April 7, 2020). Washington, DC: The National Academies Press. 2020
Study type
Country Worldwide
Funding Details Not clear
Transmission mode Meteorological
Exposures Temperature and Humidity

Bottom Line

Evidence suggests reduced transmission in high ambient temperatures and humidity, but it is limited and inconsistent.

Evidence Summary

Some evidence suggests high temperatures and humidity can slow the transmission rate. The authors note that “Given the lack of immunity to SARS-CoV-2 across the world if there is an effect of temperature and humidity on transmission, it may not be as apparent as with other respiratory viruses for which there is at least some preexisting partial immunity”

What did they do?

This is a short report described as a rapid expert assessment,  in which published and unpublished laboratory and ecological studies are reviewed. A protocol, a  search strategy and a quality appraisal are not included.

Included published studies:

  1. Chin et al. Stability of SARS-CoV-2 in different environmental conditions. Lancet Microbe 2020.
  2. Qi et al. 2020. COVID-19 transmission in Mainland China is associated with temperature and humidity: A time-series analysis
  3. Wang et al. 2020. High temperature and high humidity reduce the transmission of COVID-19.
  4. Ficetola and Rubolini. 2020. Climate affects global patterns of COVID-19 early outbreak dynamics.
  5. Islam et al. 2020. Temperature, humidity, and wind speed are associated with lower COVID-19 incidence.
  6. Sajadi et al. 2020. Temperature, humidity and latitude analysis to predict potential spread and seasonality for COVID-19.
  7. Notari. 2020. Temperature dependence of COVID-19 transmission.
  8. Luo et al. 2020. The role of absolute humidity on transmission rates of the COVID-19 outbreak.

Study reliability

This is a description of published work with some other unpublished studies via personal communication; it is not a systemic collection of studies. There is no search strategy or quality assessment included.

Clearly defined setting Demographic characteristics described Follow-up length was sufficient Transmission outcomes assessed Main biases are taken into consideration
No No Unclear Unclear Unclear

What else should I consider?

This is a short report reviewing some published and unpublished studies. The lack of a systematic approach to the search for studies and the lack of quality assessment limits the conclusions.  The authors note that many studies should be interpreted with caution due to the limited time during which experiments have taken place.

About the authors

Carl Heneghan

Carl is Professor of EBM & Director of CEBM at the University of Oxford. He is also a GP and tweets @carlheneghan. He has an active interest in discovering the truth behind health research findings

Elizabeth Spencer

Dr Elizabeth Spencer; MMedSci, PhD. Epidemiologist, Nuffield Department for Primary Care Health Sciences, University of Oxford.

Tom Jefferson

Tom Jefferson, epidemiologist.