Transmission of SARS to healthcare workers. The experience of a Hong Kong ICU

Abstract

Objective: To describe the extent and temporal pattern of transmission of severe acute respiratory syndrome (SARS) to intensive care unit staff.

Design: Retrospective observational cohort study.

Setting: University hospital intensive care unit, caring solely for patients with SARS or suspected to have SARS.

Participants: Thirty-five doctors and 152 nurses and healthcare assistants who worked in the ICU during the SARS epidemic.

Interventions: Infection control measures designed to prevent transmission of disease to staff were implemented.

Measurements and results: Sixty-seven patients with SARS were admitted to the intensive care unit. Four nurses and one healthcare assistant contracted SARS, with three of these developing symptoms within 10 days of admission of the first patient with SARS. Doctors were exposed to patients with SARS for a median (IQR) of 284 (97-376) h, while nurses and healthcare assistants were exposed for a median (IQR) of 119 (57-166) h. The ICU did not meet international standards for physical space or ventilation.

Conclusions: In an ICU in which infection control procedures are rigorously applied, the risk to staff of contracting SARS from patients is low, despite long staff exposure times and a sub-standard physical environment.

Fig. 1

Floor plan of the ICU. The on-call rooms (On call rm) were not used by resident medical staff during the SARS outbreak (PPE personal protective equipment)

Fig. 2

Time of introduction and discontinuation of various infection control measures. (NIPPV non-invasive positive-pressure ventilation, N95 use of negative-pressure respirator of N95 standard or higher)

Fig. 3

Temporal distribution of admissions

Fig. 4

Number of patients in the ICU on any given day. The number is the total number of patients who were present in the ICU at any time on the given day and therefore may exceed the bed capacity of the ICU