Some Hard-Learned Lessons About SARS
Report tracks how the disease spread in Hong Kong hospital
(HealthDay is the new name for HealthScoutNews.)
MONDAY, Aug. 4, 2003 (HealthDayNews) -- A new study that tracked how SARS spread through a Hong Kong hospital provides valuable clues for stemming an epidemic, should the potentially fatal respiratory virus strike again.
And that, health experts warn, is quite likely.
Hong Kong researchers tracked the 41 workers in a community hospital who fell ill with SARS -- severe acute respiratory syndrome -- during a six-week period earlier this year.
SARS is believed to have emerged from southern China last fall and quickly infected about 8,000 people in 29 countries, killing more than 800, most of them in Asia.
Since the disease first surfaced, scientists have discovered that a newly identified coronavirus is its cause, and the virus is spread mainly by droplet transmission -- through sneezing or coughing, for example -- and direct contact with infected persons.
In the study, the researchers found 32 of the infected hospital workers had direct contact with SARS patients, two had contact with coworkers, three had contact with both coworkers and patients, and three maintenance workers had no contact with patients.
Those most likely to be infected were health-care assistants, who were most often giving patients personal care. Next came doctors and nurses, the researchers found.
All the employees said they used masks during contact with SARS patients, leading the researchers to conclude that masks alone can't contain the disease.
"The most surprising finding from our study is that none of the family members of infected staff was infected," says Dr. Moira Chan-Yeung, a professor in the Department of Medicine at the University of Hong Kong.
"They [the staff] presented to the hospital early for isolation and treatment," she adds.
The researchers report their findings Aug. 5 in the early online issue of the Annals of Internal Medicine; it will be published in the Oct. 7 print edition.
From the study, the researchers learned a number of control measures are important to prevent the spread of SARS in hospitals, Chan-Yeung says. All patients with SARS should be treated in isolation units, and patients seen in the emergency department with probable SARS cases should be admitted to isolation wards.
"The use of nebulizers and any procedure that might induce cough, such as bronchoscopy and sputum induction in these patients, should be avoided," she says.
"There should be a high index of suspicion for the disease," she adds.
In an editorial accompanying the study, Drs. Richard P. Wenzel and Michael B. Edmond of Virginia Commonwealth University say other possible means of transmitting the virus, besides droplets and direct patient contact, need to be considered. They include blood transfusions or sharp injuries, because the virus can be found in blood, saliva, tears, urine and feces.
Health-care workers should use gowns, gloves, face shields and the highly protective N-95 masks, Wenzel and Edmond say.
Another major issue, says Edmond, is setting up isolation rooms with special air-processing systems so air isn't re-circulated to other rooms or hallways. "Many hospitals have a very limited number of these rooms, and they may be geographically scattered," he says.
"Each hospital needs to develop a plan for the management of health-care workers who are inadvertently exposed to SARS patients without protective gear," Edmond adds.
An unrelated report released last week by the U.S. General Accounting Office warned that a large-scale resurgence of the disease would pose a challenge for the nation's health-care system.