Since the COVID-19 outbreak began, health experts have emphasised how important it is to wash your hands, disinfect surfaces and cough into your arm or sleeve. But it’s hard to avoid all methods of transmission, so much so that the vast majority of people around the world are taking lockdown, quarantine or social distancing measures.
That said, most of us will have to leave the house at some point during this outbreak ― to go to the pharmacy, the grocery store or the doctor, for example. So where, then, can you pick up the virus?
According to new research published in The New England Journal of Medicine, scientists were able to show that aerosolised (that is, airborne) particles could spread the novel coronavirus. This means there’s possible airborne transmission of the illness, at least in certain settings.
Does “respiratory droplet” sound a lot like “aerosolised particle”? If you’ve heard both terms tossed around, here’s the difference and a breakdown of what mode of transmission is the most contagious.
Particle vs. droplet: Which is more infectious?
Aerosolised particles are not the same as respiratory droplets. They are much smaller, basically microscopic, said S. Wesley Long, medical director of diagnostic microbiology at Houston Methodist Hospital. (Fog is a good example of an aerosolised particle.)
Such particles linger in the air. “They can travel long distances and can be easily breathed into the lungs,” Long said. “Respiratory droplets tend to be about 20 times bigger, and travel around six feet or less before dropping to the ground.”
You will probably only encounter aerosolised particles in certain conditions, and there’s likely a very low risk of infection via aerosols for the average person. But, as the study shows, they are “concerning” because they can stay suspended in the air for several hours, said Jennifer Hanrahan, an associate professor of medicine and chief of infectious diseases at the University of Toledo.