Infection of healthcare workers with the severe acute respiratory syndromeassociated coronavirus (SARS-CoV) is thought to occur primarily by either contact or large res- piratory droplet transmission. However, infrequent health- care worker infections occurred despite the use of contact and droplet precautions, particularly during certain aerosol- generating medical procedures. We investigated a possible cluster of SARS-CoV infections in healthcare workers who used contact and droplet precautions during attempted cardiopulmonary resuscitation of a SARS patient. Unlike previously reported instances of transmission during aerosol-generating procedures, the index case-patient was unresponsive, and the intubation procedure was performed quickly and without difficulty. However, before intubation, the patient was ventilated with a bag-valve-mask that may have contributed to aerosolization of SARS-CoV. On the basis of the results of this investigation and previous reports of SARS transmission during aerosol-generating procedures, a systematic approach to the problem is out- lined, including the use of the following: 1) administrative controls, 2) environmental engineering controls, 3) person- al protective equipment, and 4) quality control. D uring the global spread of severe acute respiratory syndrome (SARS) (15), a great deal was discovered about the illness and the SARS-associated coronavirus (SARS-CoV) (6,7). SARS-CoV infection is thought to occur primarily by either contact or large respiratory droplet transmission (3,8). However, despite the use of infection control precautions and personal protective equipment designed to prevent contact and droplet trans- mission, episodes of SARS-CoV transmission to health- care workers have continued to occur under certain cir- cumstances. Of particular concern are procedures performed on SARS patients that may aerosolize SARS-CoV and lead to limited airborne transmission or enhanced contact and droplet transmission (9). Such procedures include nonin- vasive positive pressure ventilation (BiPAP), intubation, and high-frequency oscillatory ventilation. As a result, special infection control procedures have been recom- mended for aerosol-generating procedures (10,11). We present the results of an investigation of the first reported transmission of SARS-CoV to healthcare workers that occurred during attempted cardiopulmonary resuscitation of a completely unresponsive SARS patient. On the basis of the results of this investigation, as well as previous reports of SARS transmission during aerosol-generating procedures, we used the continuous quality improvement framework (12) to suggest interventions for preventing future episodes of transmission. Methods Data were collected through interviews of healthcare workers present during the attempted cardiopulmonary resuscitation where transmission of SARS-CoV was thought to have occurred. Interviews included a structured questionnaire component. Hospital and provincial policies Possible SARS Coronavirus Transmission during Cardiopulmonary Resuscitation Michael D. Christian,* Mona Loutfy, L. Clifford McDonald, Kenneth F. Martinez, Mariana Ofner,* Tom Wong* Tamara Wallington,*# Wayne L.Gold,* Barbara Mederski, Karen Green,* and Donald E. Low,* on behalf of the SARS Investigation Team1 Emerging Infectious Diseases www.cdc.gov/eid Vol. 10, No. 2, February 2004287 RESEARCHINFECTION CONTROL 1L.C. McDonald, K. Martinez (Centers for Disease Control and Prevention), Z. Abbas, D. Anderson, K. Dunn, R. Farmer, L. Gardiner, D. Gravel, L. Hansen, L. Maheux, M. Ngyuen, M. Ofner, C. Oxley, L. Srour, T. Tam, A. King, T. Wong (Health Canada), M. Loeb, L. Mandell (McMaster University), J. Farley, B. Mindell (Ontario Ministry of Health and Long Term Care), D. Low, M. Christian, A. McGeer (University of Toronto), B. Mederski (North York General Hospital), B. Henry, B. Yaffe, R. Shahin, L. Berger, T. Wallington, T. Svoboda, S. Basrur, M. Finkelstein, V. Pietropaolo (Toronto Public Health), J. Conly (University of Calgary), L. Nicolle (University of Manitoba) *University of Toronto, Toronto, Canada; University Health Network,Toronto, Canada; North York General Hospital, Toronto, Canada; Centers for Disease Control and Prevention, Atlanta, Georgia, USA; Health Canada, Ottawa, Canada; and #Toronto Public Health, Toronto, Canada *Mount Sinai Hospital Toronto, Toronto, Canada in place at the time of the resuscitation were reviewed. The hospital patient-care environment was inspected by a team of environmental engineers and industrial hygienists. Laboratory specimens, collected with nasopharyngeal swabs, were obtained from healthcare workers with symp- toms that fulfilled the SARS clinical case definition after exposure during the attempted cardiopulmonary resuscita- tion. These were tested by reverse transcriptasepoly- merase chain reaction (RT-PCR) with primers specific for SARS-CoV (7). After participants gave informed consent, convalescent-phase s