Objective: Investigate the features of outbreak epidemic, clinical disease progression of the first SARS cases in Beijing and evaluate the efficacy of therapeutic regimen.

Methods: Twenty-nine patients (11 men and 18 women, 20 - 74 years old age range) were diagnosed with infectious SARS and admitted in our hospital from the March 5th to April 14th, 2003 in this study. The data of clinical presentation and disease progression of all the patients including index subject as the infectious SARS resource patient, her family infected members and 21 health care workers were abstracted.

Results: The first SARA outbreak in Beijing was characterized with the cluster feature of resource patient family members and health care providers. The incubation period ranged from 2 to 14 days. All the patients had a fever (temperature > 38 degrees C for over 24 hours) and other manifestations as reported before. Serial chest radiographs showed progressive pathologic air-space disease. Twenty patients showed the severe syndrome with various time ranged from 1 day to 14 days. Two patients died of progressive acute respiratory distress disease. The histologic analysis of one death patient showed diffuse alveolar damage in the two lungs. Twenty-six patients receiving the combined therapy including use of corticosteroid, antiviral ribavirin agents after the onset of symptoms and showed they had an acute self-limited disease course. The oldest patient (74 year old, male) received the healthy convalescent plasma infusion (50 ml) from recovered SARS subject and completely recovered within 21 days, having a shorter disease course.

Conclusion: SARS is a kind of new self-limited and acute infectious disease. Early diagnosis, early isolation, early antiviral therapy for patients and efficient prevention for health care providers are urgently recommended. In particular, a combinational therapy of use of antiviral agents, preventive antibacterial antibiotics and pulsed dosage of corticosteroid can efficiently raise the clinical recovery rate and decrease mortality of SARS patients.