Knowing that an invisible, infectious virus may be lingering in the air of a stuffy room is an unsettling thing.
But even more unsettling is not knowing it could be there.
At the beginning of the COVID-19 pandemic, much of the world was unaware the SARS-CoV-2 coronavirus could be transmitted through the air. Following public health guidance, we dutifully washed our hands and kept our distance; some of us disinfected surfaces and even our groceries.
But the coronavirus was not just transmitted through short-range droplets emitted through coughing or sneezing.
Aerosol and atmospheric scientists from around the world were the first to sound the alarm on airborne transmission of coronavirus: Fine aerosol particles carrying the virus could linger and accumulate in the air for minutes to hours. Anyone sharing the space—even if they were farther away than the social distancing standard of 2 meters (6 feet)—could be at risk for inhaling these infected air particles.
But even before we began masking and avoiding crowded spaces, bad indoor air quality was already responsible for millions of deaths and debilitating health issues. And though we spend 90% of our time indoors, there is generally a lack of appreciation and awareness of the importance of the air around us. The composition of our indoor air matters to our health, whether it contains novel coronavirus or pollutants. But unlike outdoor air, the quality of the air we breathe indoors is not regulated.
If water is contaminated, we can still purchase bottled water, said Lidia Morawska, a physicist at Queensland University of Technology in Australia who runs an air quality lab specializing in airborne particulate matter. “But we have absolutely no choice on air we breathe. And we breathe continuously: If we stopped breathing for 3 minutes, we’ll die. That’s the importance of indoor air quality,” she said.
The revelation that COVID-19 can spread through the air could provide the attention and momentum needed to clear our indoor air for good. Some countries, such as Taiwan, already have regulations addressing indoor air quality. Others, such as Finland, are pursuing a holistic strategy involving health care and educational outreach as well as standards for managing air quality in indoor environments. In March 2022, the Biden administration launched the Clean Air in Buildings Challenge, calling on building owners and operators to adopt key strategies for improving indoor air quality as part of a broader strategy for reducing the spread of COVID-19.
Heightening interest in indoor air quality could save millions of lives—and prepare us for the next airborne pandemic.
“You know, it’s really too bad [awareness] took so long to get here,” said Linsey Marr, an expert on airborne transmission of viruses at Virginia Polytechnic Institute and State University. “But at the same time…I thought it would take a generation, I thought it would take 30 years for us to come this far if there had not been a pandemic.”