This editorial from the BMJ goes over the clinical signs and symptoms of Sudden Acute Respiratory Syndrome- a new disease causing global alarm. The disease is thought to be a new type of influenza. It is highly infectious (a greater than 50% transmission rate from patients to healthcare workers), and has an incubation period of about a week. Early symptoms typically include fever, malaise, myalgia, headache, and dizziness. About 5 days later a nonproductive cough begins. CXR findings typically are small, focal unilateral diffuse infiltrates. CXR findings are subtle and often overlooked initially. Lymphocytopenia with an elevation in LFT's may occur. No treatments have been proven effective beyond ventilatory support. Steroids and intravenous ribavirin have been used, and may be of help (this is suspected but unknown). The case fatality rate is about 3%. Comment: this is a disease where quarantine may be the only cure. The high transmission rate (50% + ) and fatality rate ( 1 in 33 die ) require that we take an aggressive approach to this illness. The BMJ editorial is excellent. **** [ bmj.com Zambon and Nicholson 326 (7391): 669 ]