Background: During outbreaks, hospital workers are at high risk for nosocomial infection with severe acute respiratory syndrome (SARS)-associated coronavirus.
Objective: To examine how hospital workers became infected and whether they transmit the virus to their families.
Design: Retrospective descriptive study.
Setting: 529-bed community hospital in Hong Kong.
Patients: 40 hospital workers infected with SARS-associated coronavirus over a 6-week period (25 March through 5 May 2003).
Measurements: Percentage of infected hospital workers according to job category.
Results: The cumulative incidence was highest among health care assistants, followed by physicians and nurses (8%, 5%, and 4%, respectively). Most hospital workers were infected from direct contact with patients with SARS, who primarily were in general wards and had unsuspected infection. At the time of contact, all hospital workers had used masks but not necessarily other protective devices. Affected hospital workers did not infect their families.
Conclusion: Before isolation of all patients with clinically confirmed or suspected SARS, routine use of several protective devices, and training of staff in infection control, many health care workers were infected with SARS from patients with unsuspected cases.