Now that we’re in the sweltering part of the summer, air conditioners are pretty much running nonstop. What impact will that have on the spread of the coronavirus? Do we need to worry about air conditioning causing infections?
Dr. Prescott Prescribes
Certain infectious agents, most notably the bacteria that cause Legionnaires’ disease, live and spread through the water in air-conditioning systems. Fortunately, to date, we’ve seen no evidence the SARS-CoV-2 coronavirus does this.
Still, that doesn’t mean air conditioning can’t play a role in spreading the virus.
In a limited field study from China, researchers found evidence that an air-conditioning unit likely played a role in spreading the virus from one infected individual to customers at other tables in a restaurant. The only path for transmission the scientists could identify was airflow, as the individuals had no other interactions, and contact tracing identified no other potential sources of infections for the patrons who subsequently got sick.
In late June, Harvard researchers hypothesized that air conditioning also has played a role in the new surge of cases in the U.S. In particular, we’ve seen surges in the South and West, with many outbreaks traced to indoor spaces like bars and restaurants that rely on air conditioning for ventilation in the summer.
This would make sense, as we know that the virus can be passed by droplets that hang in the air after we breathe them out. Frequent air exchange between indoor and outdoor sources, which happens best when windows are open, disperses those droplets and the viral particles in them.
However, on triple-digit days, no one is opening windows. Instead, droplets can linger in the air, with air conditioning recirculating them. That gives anyone in the path of that air the chance to breathe in the particles, until they eventually drop to a surface, get caught in an air filter, or are sent outside via air exchange.
I’m not suggesting you shun air conditioning this summer. I mean, come on. It’s Oklahoma!
But you should avoid crowded indoor spaces. And wear your mask.
A mask may not keep you cool, but it will help protect others. And, perhaps, you, too.