Yesterday, the U.S. Centers for Disease Control and Prevention confirmed the first case of Ebola to be diagnosed in the United States, at a hospital in Dallas. While that might seem frightening, the reality is there’s no need to panic.

Here, Amesh Adalja, MD, an infectious disease specialist at the University of Pittsburgh Medical Center, explains why:



The virus doesn't spread easily

Unlike diseases such as measles or influenza, which are spread through the air and thus can easily be transmitted through sneezing and coughing, you can only contract the Ebola virus via a contaminated person’s blood or other bodily fluids—and even then, they have to get inside of your body through your mouth, eyes, nose, or a cut, Dr. Adalja says. While the CDC and Texas health officials have been tight-lipped about the patient, it’s highly likely he was in close contact with someone else who had the virus.



You can’t be a silent carrier

While some illnesses have an incubation period during which you can unknowingly infect others, Ebola is not contagious until the infected person is actively showing symptoms. And if that’s the case, “it’s doubtful they’d be up and about, moving around,” Dr. Adalja says. “They’d most likely be bedridden—it’s a pretty debilitating disease.”

Bottom line? If you’re sitting next to someone on a train, they probably don’t have Ebola, and even if they’re about to develop it, it’s highly unlikely they’ll be able to infect you. The patient in Texas, for example, left Liberia on an overnight flight September 19, and didn’t start showing symptoms until several days later—meaning people on the flight with him aren't at risk.



We’re prepared

Just last month, a mathematical model of Ebola transmission published in PLoS Currents: Outbreaks predicted up to an 18% likelihood that Ebola would rear its head in the United States by the end of September. “It’s the largest world outbreak in history—both the CDC and infectious disease experts knew it was only a matter of time,” Dr. Adalja says. “We’ve been on alert over the last several months, developing protocols to treat patients and prevent further spread.”

For example, hospitals now know to question any patient who shows up in an emergency room with Ebola-like symptoms—fever, severe headache, diarrhea, and vomiting—about their travel history, and, if there’s anything remotely suspicious, put them in quarantine. (Texas health officials are investigating why that didn’t happen when the man first showed up in a Texas ER on September 24.) Right now, a CDC team is in Dallas to investigate each and every person the man came into contact with and, if necessary, put them in isolation.



We know how to stop it from spreading

The main reason Ebola has spread like wildfire in Africa is because of poor hospital and funeral practices: “People are taking care of sick relatives without any protective equipment, or they’re burying family members themselves, when they are still contagious,” Dr. Adalja explains.

But we’ve had four other people in this country treated for Ebola, none of whom spread the disease to others, thanks to isolation wards and other infection-control practices that are standard in U.S. hospitals. Even more reassurance: Over the past decade, the U.S. has had five imported cases of viral hemorrhagic fever similar to Ebola, none of which ever spread, according to the CDC. “The reality is, Ebola will not find our country a hospitable place,” Dr. Adalja says.

For the latest updates on Ebola, visit the Centers for Disease Control and Prevention.