If you’ve followed the news lately, you’ve probably heard about a new illness making its way around the Middle East. Known as Middle East Respiratory Syndrome (MERS), it is caused by a coronavirus called MERS-CoV. Coronaviruses, so named due to the spikes on their surface that resemble crowns, are common viruses that typically cause uncomplicated upper respiratory infections—many colds, for example, are the result of a coronavirus. MERS-CoV, however, can be much more severe, and is often deadly.

As of this writing, close to 700 people worldwide have been diagnosed with MERS, and 30 percent them have died. Earlier this year, two visitors to Saudi Arabia came back to the US with symptoms of MERS; both were treated in hospitals and released. An additional person who had contact with one of the returning travelers was found to have MERS-CoV in his system, although it is unclear whether he contracted it from the ill person or during previous travels of his own. He did not develop full-blown MERS.

How Do You Get MERS?

The short answer? Camels. The MERS-CoV coronavirus appears to be present in approximately six percent of camels in the Middle East, according to Aileen Marty, MD, an infectious disease specialist and professor at Herbert Wertheim College of Medicine in Miami. "We know it’s in the milk and other body fluids," she says, adding that it’s unknown exactly how camels transmit the virus to humans. MERS-CoV has also been found in at least one bat in the area, making bats another potential source of transmission.

Scientists are still unsure how much of the virus an infected person has to have in her body in order to transmit the disease, but once someone has developed MERS-CoV, she can pass it on to others. The disease is transmitted though body fluids including urine, feces, tears, sweat, and saliva, so sharing utensils or drinking glasses with an infected person is risky.

What to Watch Out For

A person infected with MERS may run a fever, have a sore throat or cough, and may feel nauseated and have diarrhea. These symptoms can be indistinguishable from those of many less serious illnesses, which is why the person’s travel itinerary and contacts are of great importance in determining whether the illness is MERS.

Severe cases of MERS can progress to pneumonia and/or respiratory failure (when there’s not enough oxygen in your blood), as well as septic shock (dangerously low blood pressure caused by an infection) and organ failure, particularly kidney failure. Marty says the incubation period (the time between catching an infection and developing symptoms) is probably about seven days, but experts recommend paying attention to respiratory symptoms and fever that may appear as long as 14 days after returning from the Middle East or having close contact with someone who's been there.

How Worried Should I Be?

You shouldn’t be particularly worried about MERS unless you’re traveling to the Arabian Peninsula, Marty says—and even then, panic is not necessary. She points out that about half of the infected people in that area have been healthcare workers: "If you’re not going to be working in a hospital or visiting relatives in hospitals, your risk is pretty low," she says.

Staying Healthy

Because there’s not yet a vaccine for MERS, if you plan to travel to the Middle East and/or may have contact with camels, it’s important to follow these basic rules of hygiene to minimize your risk:

  • Wash your hands regularly.
  • Use an alcohol-based sanitizer if you don’t have access to washing facilities.
  • Avoid touching your nose, mouth, or eyes if your hands aren't washed.

Also, be especially vigilant if you have a chronic disease, are older, or if your immune system is otherwise compromised. According to Marty, the virus has been particularly devastating to people whose immune systems are weakened.

Aileen Marty, MD, reviewed this article.  


"Middle East Respiratory Syndrome." Centers for Disease Control and Prevention. Accessed June 11, 2014. 

"World-Travel Advice on MERS-CoV For Pilgrimages." World Health Organization. Accessed June 11, 2014.

Aileen Marty, MD, professor at Herbert Wertheim College of Medicine. Phone conversation with source. June 11, 2014.

"Frequently Asked Questions—Middle East Respiratory Syndrome Coronvirus (MERS-CoV)." Public Health Agency of Canada. Page modified April 25, 2014.

"Septic Shock." MedlinePlus. Page updated January 8, 2012. 

"What Is Respiratory Failure?" National Heart, Blood, and Lung Institute. Page updated December 19, 2011.