A Preliminary Result of Study on the Transmission Route of Severe Acute Respiratory Syndrome Hospital Infection

摘要

Objective To study the transmission route of Severe Acute Respiratory Syndrome (SARS) hospital infection. Methods 10 definite SARS patients were selected from a general hospital in March. Field inspection of infected places was made. And individual interview was carried out by a standardized questionnaire of China CDC. Contact history with SARS patient, place and route of infection, measures of prevention were included in the interview. Results (1) Distributions by places were confined to Ward 4,5,6 on the 7,8,12,13 and 14 floors in west unit of the inpatient building.The inpatients were older and most had severe original diseases. (2) Index patients were the first generation source of transmission and the secondary attacked inpatients and medical staffs were the second generation. The latent infected persons who had close contact with SARS patients were also possible latent sources of transmission. (3)The major transmission routes were near space droplet infection and close contact infection. There was also a clue to the probability of aerosol or droplet nuclei infection through air - condition and ventilation system. Physical experiment was carried out to confirm the possibility of SARS virus transmitting vertically through ventilation pipeline. Conclusions Hospital infection was the main epidemic form of SARS in the early stage. Aerosol transmission in the long distance was also a route of transmission of SARS virus, besides the close contact and near space airborne transmission. More epidemiological and experimental studies are need to be done in the future.