Better Ventilation Could Do Much More Than Stopping COVID

What we have learned about how easily COVID transmits in poorly-ventilated areas is also informing us how to minimize other pesky airborne ailments such as colds and flu.

In official public-health guidance, however, the possibility of flu-laden aerosols still barely gets a mention. The CDC and WHO guidelines focus on large droplets that supposedly do not travel beyond six feet or one meter, respectively. (Never mind that scientists who actually study aerosols knew this six-foot rule violated the laws of physics.) The coronavirus should get us to take the airborne spread of flu and colds more seriously too, says Jonathan Samet, a pulmonary physician and epidemiologist at the Colorado School of Public Health. At the very least, it should spur research to establish the relative importance of different routes of transmission. “We had done such limited research before on airborne transmission of common infections,” Samet told me. This just wasn’t seen as a major problem until now.

Earlier this year, Morawska and dozens of her colleagues in the fields of building science, public health, and medicine published an editorial in Science calling for a “paradigm shift” around indoor air. Yes, vaccines and masks work against the coronavirus, but these scientists wanted to think bigger and more ambitious—beyond what any single person can do to protect themselves. If buildings are allowing respiratory viruses to spread by air, we should be able to redesign buildings to prevent that. We just have to reimagine how air flows through all the places we work, learn, play, and breathe. 

The question boils down to: How much disease are we willing to tolerate before we act? When London built its sewage system, its cholera outbreaks were killing thousands of people. What finally spurred Parliament to act was the stench coming off the River Thames during the Great Stink of 1858. At the time, Victorians believed that foul air caused disease, and this was an emergency. (They were wrong about exactly how cholera was spreading from the river—it was through contaminated water—but they had ironically stumbled upon the right solution.)

How much actually changes “depends on the momentum created now,” she said. She pointed out that the vaccines looked like they were going to quickly end the pandemic—but then they didn’t, as the Delta variant complicated things. The longer this pandemic drags on, the steeper the cost of taking indoor air for granted.