SAQ: How could weather and temperatures affect COVID-19?

The jury is still out, but coronavirus likely won’t behave like the flu

Coronavirus molecule
Coronavirus molecule (CNN)

While there have been assertions that weather will have an effect on the spread of COVID-19, the virus is so new that many questions remain without a definitive answer.

Scientists are working to find out whether the coronavirus might be impacted by temperature or other weather-related factors, so we’ll run through some of the findings so far.

First and foremost, the World Health Organization has put out some myth-busters when it comes to the weather and COVID-19.

Ultimately, “there is no reason to believe that cold weather can kill” the virus and “from the evidence so far, the new coronavirus can be transmitted in ALL areas, including areas with hot and humid weather,” according to the World Health Organization.

SAQ: COVID-19 vs. seasonal flu: Why novel coronavirus is much worse

Myth-buster from the World Health Organization

While much more data is needed to understand any significant impact, a few studies have been conducted that are revealing clues.

One recent research paper noted that significant community spread is occurring "in cities and regions along a narrow east-west distribution roughly along the 30°-50° N’ corridor at consistently similar weather patterns”. Temperatures in this region averaged 41° to 52°.

This corridor includes much of the United States, China, and central Europe. Italy and Wuhan, China, some of the hardest hit regions, lie in this zone.

San Antonio sits at 29.4° N, just south of the of 30th parallel. It is possible that areas within this region may be facing a higher chance of community spread, according to the study.

Another study, published by the Sun Yat-sen University in Guangzhou, China, also believed that temperature could play a role in the spread of the virus. It asserted that the “virus is highly sensitive to high temperature”. It suggested that “countries and regions with a lower temperature adopt the strictest control measures”. This study has not yet been peer-reviewed.

Meantime, an additional study by a group of researchers, including epidemiologist Marc Lipsitch from Harvard’s T.H. Chan School of Public Health, agreed with the WHO. It found that patterns of COVID-19 are “not completely consistent with the hypothesis that high absolute humidity may limit the survival and transmission of this new virus”. The study goes on to conclude that “sustained transmission and rapid (exponential) growth of cases are possible over a range of humidity conditions ranging from cold and dry provinces in China”.

In short, it found that the virus can survive in just about any climate, regardless of humidity level.

Marc Lipsitch, via the Center for Communicable Disease Dynamics, also said this: “The short answer is that while we may expect modest declines in the contagiousness of SARS-CoV-2 in warmer, wetter weather and perhaps with the closing of schools in temperate regions of the Northern Hemisphere, it is not reasonable to expect these declines alone to slow transmission enough to make a big dent”.

The bottom line is that there are many factors at play here, in addition to weather. Sunlight and amount of UV may also play roles with the spread of COVID-19.

It is also important to note that the World Health Organization has said that the spread of the virus through mosquitoes or ticks is not a concern.

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About the Author:

Justin Horne is a meteorologist and reporter for KSAT 12 News. When severe weather rolls through, Justin will hop in the KSAT 12 Storm Chaser to safely bring you the latest weather conditions from across South Texas. On top of delivering an accurate forecast, Justin often reports on one of his favorite topics: Texas history.