SKYROCKETING CASES PROVE SUMMER, HEAT ARE NO BARRIER TO COVID-19
Any hopes that summer’s high temperatures might slow the spread of the coronavirus were smashed in June and July by skyrocketing cases across the country, especially in some of the warmest states.
Colin Carlson wasn’t a bit surprised that summer heat failed to curb the virus that causes COVID-19, which has claimed more than 140,000 lives in the U.S. That notion, no matter how many times it was repeated, was never supported by science, said Carlson, an assistant research professor at Georgetown University who studies the relationship between climate change and infectious disease.
The optimistic, though inaccurate forecast was among several persistent misconceptions about heat and light, and other issues related to the spread of the virus, that leave epidemiologists like Carlson increasingly frustrated. They see and hear mixed messages and miscommunications all the time, whether it’s in social media, their circle of friends and family, hastily assembled research papers or the White House.
“My hunch is that most Americans think sunlight and heat kill the virus and you can be outdoors without risk,” Carlson said, but if you’re in a group, even outside, you can spread and contract the virus.” It’s true that not being in a confined space is better but it’s not protective.”
Clearing up conflicting messages about how the virus spreads could help bring it under control, said Jamie Slaughter-Acey, an assistant professor in the division of epidemiology and community health at the University of Minnesota.
“We’ve had this mixed messaging from Day One,” said Slaughter-Acey. “The longer those mixed messages linger in conversation, the more it undermines practices such as wearing a mask, using hand sanitizer and staying six feet apart if possible.”
For example, she and others pointed to theories that the virus would go away in the summer like the flu.
When a disease like COVID-19 is spreading, people have a tendency to “want to grasp at whatever thing they can see that might be a cure, or a reason it’s safe,” said Sadie Jane Ryan, an associate professor of medical geography at the University of Florida.
Marshall Shepherd, director of the atmospheric science program at the University of Georgia, calls it “wishcasting.”
“People ‘wishcast’ scenarios in our minds, but they don’t jibe with what the science or the data is actually bearing out,” Shepherd said. “The science has been very clear, we don’t understand the relationship between heat and COVID.”
It should have been obvious in the begin
“NINETY-NINE PERCENT OF THE VIRUS WILL DISAPPEAR IN DIRECT SUNLIGHT, BUT IT WILL TAKE 30 TO 40 MINUTES. IF ONE VIRUS PARTICLE GETS YOU SICK, IT’S GOING TO TAKE A LONG TIME FOR THAT VIRUS TO GO AWAY.” LLOYD HOUGH, Homeland Security scientist
ning, he said, when the virus began taking off in some Southeastern states even as they experienced record-breaking heat.
Then, during the first week of July, nine of the 10 states with the biggest increases in cases were in the Sunbelt, including Florida, Texas and Arizona, according to case information from the Centers for Disease Control and Prevention. Of those states, Florida had the warmest temperature in June, with an average of 81 degrees, followed by Texas with an average of 80.6 degrees.
After studying the potential impacts of climate on the spread of COVID-19 earlier in the year, Rachel Baker, a post-doctoral researcher at Princeton University, and a team of colleagues concluded at some point in the future the virus could become seasonal like the flu. However, the paper they published made it clear that in this early stage, a lack of immunity among the population would be the fundamental driver.
The virus “just spreads really well whether you’re inside or outside,” Baker said.
Homeland Security scientists have also continued to study the virus. They’ve evaluated its stability and ability to survive in saliva, lung fluids, on non-porous surfaces and in the air, said the team’s lead scientist, Lloyd Hough.
They said their research showed sunlight and temperature can break the virus down faster on non-porous surfaces such as shopping carts, but it’s not instant. Hough said it is just one small piece of the many characteristics that contribute to the ability of the virus to transmit and cause disease.
“Ninety-nine percent of the virus will disappear in direct sunlight, but it will take 30 to 40 minutes,” he said. “If one virus particle gets you sick, it’s going to take a long time for that virus to go away.”
As a practical example, he said, “if you’re going to the supermarket, the shopping cart that has been sitting out in the sun is probably safer than the shopping cart that has been sitting inside the store.”
Heat and sunlight don’t impact the virus inside the human body, Hough said. They haven’t studied its survival on skin, and many other unknowns remain. It’s not known exactly how much virus a sick person puts into the air when they cough, he said, or how much of that virus it takes to make someone sick.
“Any two people in the world can spread COVID-19 to each other at any time, which means, in a population with no immunity, weather isn’t at the steering wheel,” Carlson said.