If someone sneezes on a bus, you’ll see everyone nearby hold their breath and look away in fear of seeing something gooey somewhere in the vicinity. It’s extraordinarily ew, but like most gross bodily functions, sneezes have their purpose too.
So, I guess we might as well use technology to study the germ-infested human spray closer.
Mathematical physicist Lydia Bourouiba has created a slo-mo sneeze video to monitor how far the droplets spray, in turn giving researchers a better idea of how they can control the spread of disease. Because, as we are all hopefully aware, sneezes are made up of saliva and mucus, which carry viruses and bacteria.
What less of us probably know is that the stuff that it’s only really an educated guess to say that if we stand out of the way of someone else’s oncoming sneeze cloud, we are less likely to pick up the germs.
Bourouiba is head of the Fluid Dynamics of Disease Transmission Laboratory at MIT and has spent her academic career studying the infectious spray of disgusting mist we call a sneeze, according to Rae Ellen Bichell at NPR.
Speaking of what she and her colleagues found by analysing the sneezes in the slow-mo black and white video, Bourouiba said “There’s a whole range of droplet sizes in this cloud, and the cloud is made of hot and moist air.
“And it’s turbulent, so that means that it has swirls and eddies, and it’s moving very fast.”
The goal of the study is to get into the crunch of how sneezes travel in different conditions. According to Bourouiba, the tiny droplets can actually travel across a room, very quickly, and linger in the air for a few minutes at a time. Blurgh!
“So, for example, in a typical hospital room, with a given ambient temperature and moisture and a given airflow, what is the ultimate distribution of the position of these droplets and the pathogens they contain?” Bourouiba said. “And if we change the room and ventilation and different environmental conditions, how does that change?”
After reading that Bourouiba’s own personal technique of minimising momentum and travel distance of flying sneeze particles is to go straight into her elbow, I’m happy to offer my own technique of going straight down the top of my shirt. You can have that one for free.