It is well known that rates of transmission of some respiratory viruses, including influenza, tend to fall during the summer months.
It is well known that rates of transmission of some respiratory viruses, including influenza, tend to fall during the summer months. As COVID-19 has spread across the globe, questions have been raised about whether warming temperatures, humidity and UV index might slow, or even halt, the spread of SARS-CoV-2, the virus that causes COVID-19. These effects on virus transmission will be important to understand as warmer months ease in and states across the country consider and implement reopening plans.
To answer these questions, researchers at Mount Auburn Hospital looked at the impact of temperature, precipitation, and UV index on COVID-19 case rates in the United States during the spring months of 2020. Published in the journal Clinical Infectious Diseases, the findings reveal that while the rate of COVID-19 incidence does decrease with warmer temperatures up until 52 degrees F, further warmer temperatures do not decrease disease transmission significantly. A higher UV index also assists in slowing the growth rate of new cases, but the overall impact remains modest. Precipitation patterns did not appear to have any effect on virus transmission.
The research team analyzed daily reported cases of SARS-CoV-2 infection across the United States from January 22, 2020 through April 3, 2020, as tracked by John Hopkins University’s COVID-19 Dashboard, and estimated associations between temperature, precipitation, UV Index, as tracked from the National Centers for Environmental Information, and rate of case increase.
“While the rate of virus transmission may slow down as the maximum daily temperature rises to around 50 degrees, the effects of temperature rise beyond that don’t seem to be significant,” said first author Shiv T. Sehra, MD, Director of the Internal Medicine Residency Program at Mount Auburn Hospital and Assistant Professor of Medicine at Harvard Medical School. “Based on our analysis, the modest association suggests that it is unlikely that disease transmission will slow dramatically in the summer months from the increase in temperature alone.”
Read more at Mount Auburn Hospital
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