The ongoing fight against the COVID-19 pandemic could get a boost if Canadians paid more attention to the relative humidity levels in public and private spaces, according to a growing body of international research.
Doctors, scientists and engineers agree that sufficient indoor air moisture levels can have a powerful but little-understood effect on the transmission of airborne diseases. While the novel coronavirus that causes COVID-19 is currently treated as one that’s transmitted through droplet infection rather than the air, research on exactly how it passes between humans is still underway.
Most buildings, however, fall short of the recommended threshold of 40 to 60 per cent relative humidity, particularly in countries with colder, dryer climates such as Canada.
Addressing the issue now, they contend, could confer some immediate short-term benefits and offer a powerful tool for warding off similar epidemics in the future.
“Transmission is greater in dry air, infectivity is higher in dry air, and the ability of a human being to fight infection is impaired,” said Dr. Stephanie Taylor, a graduate of and lecturer at Harvard Medical School. “Any one of those would be important, but all three of them are in play.”
Taylor concedes that the notion may seem counter-intuitive, saying the idea of humidity conjures images of fetid swamps and disease-bearing mosquitoes. But she said a growing body of research has suggested that relative humidity levels that are much more comfortable for humans offer a host of benefits.