Middle East Respiratory Syndrome (MERS) is a respiratory illness caused by a virus (more specifically, a coronavirus) called Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and has been recently recognized in humans.

It was first reported in Saudi Arabia in 2012 and has since spread to several other countries, including the United States. Most people identified as infected with MERS-CoV developed severe acute respiratory illness, including fever, cough and shortness of breath. Many of them have died.

So far, all cases of MERS have been linked through travel to, or residence in, countries in and near the Arabian Peninsula. The largest known outbreak of MERS outside the Arabian Peninsula occurred in the Republic of Korea in 2015. The outbreak was associated with a traveler returning from the Arabian Peninsula.

MERS-CoV has spread from ill people to others through close contact, such as caring for or living with an infected person.

MERS can affect anyone. MERS patients have ranged in age from younger than 1 to 99 years old.

CDC continues to closely monitor the MERS situation globally and work with partners to better understand the risks of this virus, including the source, how it spreads and how infections might be prevented. CDC recognizes the potential for MERS-CoV to spread further and cause more cases globally and in the U.S. We have provided information for travelers and are working with health departments, hospitals and other partners to prepare for this. 

MERS Fact Sheet