U00-U49: Provisional assignment of new diseases of uncertain etiology or emergency use

U04: Severe acute respiratory syndrome [SARS]

Severe Acute Respiratory Syndrome (SARS) is a contagious, sometimes fatal condition caused by a type of coronavirus, known as SARS-associated coronavirus (SARS-CoV). This virus is usually spread through close contact with an infected person's respiratory droplets, such as those produced when coughing or sneezing. The main symptoms of SARS include a high fever, chills, headache, body aches, and later in the disease progression, pneumonia often develops that can cause difficulty breathing. The lungs are the main organ system affected by SARS, although the virus can also affect other body systems, such as the heart and liver. SARS starts to show symptoms generally within two to seven days after being infected with the virus. The disease may progress rapidly, and severe cases can lead to respiratory failure, which can be life-threatening.