Study Shows Climbing Fatality Rate for SARS

An epidemiologic study conducted by UK epidemiologists and scientists from Hong Kong reveals a much higher mortality rate for severe acute respiratory syndrome (SARS) than initially reported, especially among older patients. The study was published in the May 7, 2003, online issue of The Lancet.

The researchers studied 1,425 cases from Hong Kong. They found that the fatality rate in patients 60 and older was 43.3%, far higher than previously reported. In patients under 60, the rate was 13.2%. Using a second method of calculation, these numbers were 55% and 6.8%, respectively. The average incubation period was found to be 6.4 days.

The study underscored the importance of reducing the time from onset of symptoms to quarantining in a hospital, which reduces transmission. Public health interventions resulted in a significant reduction in confirmed SARS cases. These interventions included encouraging patients to report to a hospital rapidly after onset of symptoms, tracing contacts of confirmed and suspected cases and quarantining them, and restricting the travel of contacts.

In The Lancet article, co-author Christl Donnelly comments, "Although this study shows that the fatality rate from SARS is higher than previously thought, we now know that public-health interventions have been successfully reducing the spread of the disease.” The study was conducted by Dr. Donnelly, Dr. Roy Anderson, and colleagues from Imperial College (London, UK) and the Department of Health in Hong Kong.