PITTSBURGH (KDKA) — The heat outside has people going inside into the air-conditioning, and the possibility of coronavirus spreading.

“How coronavirus is spread through the air is an active area of investigation. If this virus is spread by the aerosol route, that would make it higher risk to spread this way,” says Dr. Avraham Cooper, a pulmonologist and intensive care physician at the Ohio State University Wexner Medical Center. “Aerosols are smaller (than droplets) that can carry the virus further distances.”

“Those particles, they can float around literally for days,” says Neil Donahue, Ph.D., of Carnegie Mellon University and the Lord University Center for Atmospheric Particle Studies.

The CDC documented an outbreak in China that occurred this way. Restaurant diners downstream from someone with the virus and an air conditioner unit got sick. Patrons on the other side of the restaurant did not.

“What there clearly is evidence for is inside transmission within a room,” says Donahue.

When outdoor temperatures soar, to save energy, the air conditioner unit adjusts how much fresh air it brings in. With more heat outside, the more recirculated air inside.

“The more fresh air you get in a room, the more diluted those (virus) particles are going to be,” Donahue says.

To stay safe, it’s all about the outdoors.

“Being indoors without a mask on is the highest risk thing people can do right now,” says Dr. Cooper.

“Trying to have as few people in any given space as possible and for the smallest amount of time possible,” said Donahue. “I would rather be a little uncomfortable than ill.”

Masks reduce the spread of droplets and aerosols, so when you are inside around other people, wear a mask.

Dr. Maria Simbra