In February 2013, two patients with severe pneumonia and pulmonary dysfunction were admitted to Shanghai Fifth Hospital affiliated with Fudan University. The first patient, an 87-year-old man became ill on February 19th and died on February 27th. The second patient, also male and 27 years old, became ill on February 27th and died on March 4th. In both cases there were fever, cough, and respiratory tract infection during the early stages of the illness. Five to ten days later, the patients developed severe pneumonia and progressive respiratory distress with lethal outcome.