SARS is caused by novel variant of?

Severe acute respiratory syndrome is caused by coronavirus type. SARS C/F Severe lower respiratory tract infection; Characterized by muscle pain, headache, sore throat Fever followed by the onset of respiratory symptoms mainly cough, dyspnea and pneumonia. There are six coronaviruses that can infect humans: Alpha coronaviruses 229E and NL63 Beta coronaviruses OC43, HKU1, SARS-CoV and MERS-CoV