Severe acute respiratory syndrome (SARS)

Severe acute respiratory syndrome (SARS) is a serious form of pneumonia. It is caused by a virus that was first identified in 2003. Infection with the SARS virus causes  acute respiratory distress (severe breathing difficulty) and sometimes death.  
SARS is a dramatic example of how quickly world travel can spread a disease. It is also an example of how quickly a connected health system can respond to a new health threat.

MERS (Middle East Respiratory Syndrome)

MERS (Middle East Respiratory Syndrome) is a severe pneumonia-like respiratory disease caused by a virus
Pneumonia is a general term for an inflammation of the air sacs of the lungs caused by an infection or chemical. With pneumonia, the lungs fill with fluid, which interferes with their ability to transfer oxygen to the blood. MERS is known as an atypical pneumonia because it is not caused by the usual bacteria or viruses.
MERS causes high fever, cough, and severe shortness of breath. The infection is thought to be spread by close contact with an infected person.