Last Updated Jun 12, 2015 12:22 PM EDT
Doctors in the U.S. are being warned to be on the lookout for Middle East Respiratory Syndrome, the potentially deadly illness known as MERS. The Centers for Disease Control and Prevention issued the alert Thursday in the midst of an outbreak in South Korea that's sickened at least 126 people. On Friday, the death toll rose to 13.
"It's a wakeup call to everyone, because if it can go to South Korea, it can be transmitted to other countries," Dr. William Schaffner, an infectious disease specialist at Vanderbilt Medical Center, told CBS News.
It's believed that a 68-year-old man carried the illness to South Korea last month after traveling to Saudi Arabia, the country where the virus was first identified in 2012. The man visited 4 hospitals in South Korea before he was diagnosed -- exposing many other people in the process.
The disease can be spread through a cough or close contact with someone who is infected. The CDC says it's important for doctors in this country to be aware of the risk and consider the MERS virus as a possible diagnosis if a patient with respiratory symptoms recently traveled to a region where the virus is present.
"Every clinician, doctors and nurses, need to be thinking about the possibility of MERS," said Dr. Michael Bell, deputy director of the CDC. "That means if someone comes into a clinic or an emergency room with a fever and cough you need to ask, 'Have you traveled at all? Where have you been?'"
The symptoms of MERS are similar to other respiratory illnesses, Schaffner said: "Fever, cough, pain in your chest. But it's highly infectious."
The CDC says it's important for doctors and hospitals to develop plans to identify possible cases and isolate patients before they can infect others. It's a lesson learned from last year's Ebola outbreak. "We spent a lot of time thinking about Ebola and learned the importance of taking a good travel history. 'Where have you traveled, what kind of work do you do?' These are routine things that we don't want people to stop doing," Bell said.
There are currently no known cases of MERS in the United States. Two cases were reported in 2014, and both patients recovered.