Early SARS Transmission
• Index Case was a visitor to Hong Kong from China; ten people were exposed and transmitted SARS to other countries.
• SARS is predominantly transmitted in hospital settings.
• Close contact is the predominant mode of transmission in droplets, fomites, direct contact, and autoinoculation. Some airborne transmission may have occurred.
• Infection control practices limit transmission, even from super-spreaders.
• Transmission was controlled or stopped in Canada, Singapore, Thailand, and the United States.
• Because of success with control, patients likely transmit only when sick.
Symptoms and Illness
• Symptoms begin with fever, then cough, shortness of breath, interstitial pneumonia on X-ray, and lymphopenia.
• Illness is generally more severe with older patients.
• There is a high rate of severe illness with SARS.
• Case fatality rate is going up, mostly likely due to ways of accounting for cases.
Diagnosis and Detection Issues
• We do not yet know what the best specimen is at certain times of illness for detecting infection.
• Diagnosis to date has used electronmicroscopy, isolation of virus, detection of antigens in tissue, and detection of viral RNA by PCR.
• Virus has been detected in respiratory secretions, stool specimens, urine specimens, bronchial lavage specimens, and in lung and kidney tissue.
• Antibody has not been detected in non-SARS patients.
• SARS in immune-suppressed patients could be a problem in the future.