The Scientist: Dr. Eden V. Wells, Clinical Associate Professor of Epidemiology and Director of the Preventive Medicine Residency at the University of Michigan School of Public Health
The Answer: The Ebola outbreak is very scary, but the risk of getting the virus from a bus, train or subway is very, very low. If you were trapped in a subway car while someone was expelling diarrhea, vomit or blood next to you, then your risk would increase. But keep in mind that someone who was so blatantly ill would not be casually traveling around — he or she would be at home or in a hospital. And if a sick person were out in public? You’d see or smell it from a mile away and not let yourself get close enough to become infected. You’re not too likely to find yourself in that situation during your morning commute. Yes, hypothetically, if a person showing Ebola symptoms took a cab home after they fell ill, puked or defacated all over the seat and the driver didn’t bother having it cleaned and then you sat in it, ignoring the smell, and touched it, and then touched your face or ate a sandwich, you could get the virus. But hopefully that scenario sounds as farfetched as it is.
Ebola is spread through direct contact with blood or bodily fluids—everything from feces and urine to saliva, sweat, vomit and yes, even breast milk and semen—of an infected person, and can enter through mucous membranes or broken skin. You can also get it from an object, like a needle, that contains infected blood or fluids. Droplets expelled by a visibly ill patient can infect a person within a few feet only if the droplets come into contact with a mucous membrane or break in the skin. This is only considered a risk in a healthcare setting where workers have intimate contact with sick patients, and in communities where Ebola is circulating like West Africa. Currently, Ebola is not circulating in any community outside of Western Africa, so unless you work in a hospital with infected patients, you are not at risk of infection via droplets.
Ebola is highly infectious and just a few particles are enough to infect you. But again, its contagiousness is extremely low, since it requires very close contact with bodily fluids. Keep living your life as normal, but just be smart: Protect yourself the way you’d protect yourself against a cold or the flu (which you should be doing anyway!). Don’t touch public surfaces that look contaminated. Use an alcohol-based hand sanitizer or wash your hands after riding a bus, train or subway or touching any other surface that other people are touching. And most importantly, stay calm.