Latest Articles

Filter (by article categories)

Sneezes Are Travelling Germ Clouds

Zuzana Bleha
May 13, 2014
man sneezing

Do you assume you are safe from your colleague’s germs just because you are out of the “splatter zone”? Do you avoid the sneezing person in the office thinking if you don’t go near them, you will be okay?

Well, next time you find yourself saying “bless you” or “gesundheit” to someone as a polite response to their sneeze, you might want to consider ducking or running too. 

You’d be surprised to learn that their cough or a sneeze can carry that gross bacteria a greater distance than you think!


What you can’t see, can harm you.


Based on Journal of Fluid Mechanics, MIT researchers demonstrated that a sneeze or cough is a “multiphase turbulent buoyant cloud with suspended droplets of various sizes”, meaning that there is an invisible cloud that carries the individual droplets allowing them to travel much farther than had been suspected. These invisible droplets will travel a lot farther than the ones you can see, and they can contain potentially harmful bacteria, like strep, flu, common cold, and even measles.





MIT researchers used high-speed imaging of coughs and sneezes to analyze trajectory and mass to come to their conclusion. They found that droplets 100 micrometers (millionths of a meter) in diameter travel five times farther than previously estimated, and droplets 10 micrometers in diameter travel 200 times farther. Small droplets found in the invisible cloud of less than 50 micrometers in size - that's smaller than the diameter of a strand of hair - can frequently remain airborne long enough to reach even ventilation systems.


Air movement or air flow, like from a ventilation system or air-conditioning, plays an important role in increasing the number of microbes in the environment. That’s bad news for spaces like offices or airplanes that share a ventilation system. A sneeze can send airborne pathogens floating in the air farther, so the germs of the passenger hacking in the back of the plane, are very likely to reach surfaces near you.


So what can you do?

It can seem like there is nowhere to hide from harmful bacteria. This new information shows that the footprint for airborne bacteria can be larger than previously believed.  And because the most common way of becoming infected with a germ is by catching it from another person who is already infected, this adds yet another consideration when trying to prevent infections within the workplace.


        Download an Infection Prevention Manager's Guide

Apart from living in a bubble, educating employees on proper hand hygiene practices can help minimize infection. Dr. John Hines, Research and Development Director for Deb Group Ltd. explains that "no reliable data exists for office spaces, but in hospitals it is estimated that approximately 50% of infections could be prevented by proper hand hygiene practices. It is probably reasonable to assume a similar, or even higher, percentage may be the case in offices and other public spaces."


Proper hand hygiene practices in the workplace, can make a big difference.


"It may not feel that there is much we can do as individuals to avoid picking up airborne infections," says Hines,"however the majority of potential transmission routes are secondary, rather than primary in nature - that is transmission happen via an intermediate surface rather than directly from one host to another. This is where hand hygiene comes in - not only for the person with the infection, but for everyone. We should assume that surfaces may be contaminated and be sure to clean hands before eating as well as after 'contaminating' events such as sneezing or using the bathroom."



sneeze elbow

The Centre of Diseases Control and Prevention (CDC) recommends sneezing or coughing into a tissue and then washing hands thoroughly. At a minimum, employees should cough into the crook of their arm at all times, in order to reduce the reach of their germs. Keeping surfaces in the workplace clean by wiping them down regularly with a clean paper towel and disinfectant, as well as providing employees with hand sanitizers at or near their work space, will also help.


Finally, if an employee is exhibiting cold-like symptoms, such as regular sniffing, coughing or sneezing, it is advisable that all employees should adopt more frequent hand hygiene practices as a precaution.


See all of the CDC's recommendations and some helpful resources and tools for employers and employees here.


Read the full study here.


Subscribe to the Deb Blog
New call-to-action
Liked the article? Why not leave us a comment.