As the days get longer, the weather continues to warm up and the coronavirus numbers continue to move in a positive direction across Maryland.
But local health officials say it’s still too early to tell if there is any correlation between those things.
“We don’t have enough data and evidence to suggest that warmer weather has an impact on transmission of this coronavirus,” said Dr. Randall Culpepper, deputy health officer for Frederick County.
There is some belief in the medical community that warmer weather and sunlight help reduce the spread of the virus, and some scientific studies support that belief. But it’s too soon to draw any definitive conclusions.
“Warmer weather will partially reduce virus infections, but definitely not eliminate COVID,” said Dr. Manny Casiano, chief medical officer at Frederick Health Hospital.
“There are studies out of [Massachusetts Institute of Technology] showing that at average daily temperatures above 77 degrees, the transmission of the virus decreases due to increased humidity and [ultraviolet] radiation from the sun. So, that will help us a bit.”
Casiano pointed to the sterilization affect of UV light, as many hospitals use UV lights to disinfect rooms once patients have been discharged.
He also said the droplets of saliva that the virus rides from person to person become heavier in warmer weather because the air is more humid. As a result, they fall to the ground more quickly and don’t stay airborne as long.
That’s why he said it’s important to maintain physical distance because the virus will fall to the ground before it reaches another person.
It also explains why there is such fear of resurgence of coronavirus in the fall when the weather turns colder.
In cooler conditions, there is less humidity, and the water part of the droplets evaporates very quickly. So, the virus remains suspended in the air for a longer period of time, Casiano said.
“Warmer weather will definitely help,” he said. “But it’s not the most important factor in COVID. Many warm-climate countries are seeing significant virus spread. Brazil is now the country with the fastest growing numbers of COVID infections and deaths, despite being a warm climate.”
Rather, it’s critical that preventative measures such as physical distancing, wearing masks and staying at home as much as possible remain in place to reduce that transmission of the virus, doctors say.
Those factors, more so than the weather, are why Maryland has done such an effective job in battling COVID-19, they said.
Hospitalizations have been falling across the state for more than two weeks, and the number of new daily cases is as low as it has been since early April.
The number of confirmed deaths over the last seven days have declined by more than 25 percent over the seven previous days, according to Gov. Larry Hogan.
The amount of testing continues to improve, while the positivity rate continues to fall.
“Kudos to Gov. Hogan, County Executive Jan Gardner and all of our Fredericktonians,” Casiano said.
It’s still too early to relax or declare victory, however.
“My concern is people will be less likely to maintain the physical distancing and use of face covering as we begin to progress down the Governor’s Roadmap to Recovery,” Culpepper said.
“We are still in the middle of this pandemic, and, just like a marathon, no one would ever consider stopping the race halfway through and expect to win the race. This is not the time for us to take our foot off the pedal and relax those measures that successfully got us to this point.”