BACKGROUND: Severe acute respiratory syndrome (SARS) was introduced into Canada by a visitor to Hong Kong who returned to Toronto on Feb. 23, 2003. Transmission to a family member who was later admitted to a community hospital in Toronto led to a large nosocomial outbreak. In this report we summarize the preliminary results of the epidemiological investigation into the transmission of SARS between 128 cases associated with this hospital outbreak. METHODS: We collected epidemiologic data on 128 probable and suspect cases of SARS associated with the hospital outbreak, including those who became infected in hospital and the next generation of illness arising among their contacts. Incubation periods were calculated based on cases with a single known exposure. Transmission chains from the index family to hospital contacts and within the hospital were mapped. Attack rates were calculated for nurses in 3 hospital wards where transmission occurred. RESULTS: The cases ranged in age from 21 months to 86 years; 60.2% were female. Seventeen deaths were reported (case-fatality rate 13.3%). Of the identified cases, 36.7% were hospital staff. Other cases were household or social contacts of SARS cases (29.6%), hospital patients (14.1%), visitors (14.1%) or other health care workers (5.5%). Of the 128 cases, 120 (93.8%) had documented contact with a SARS case or with a ward where there was a known SARS case. The remaining 8 cases without documented exposure are believed to have had exposure to an unidentified case and remain under investigation. The attack rates among nurses who worked in the emergency department, intensive care unit and coronary care unit ranged from 10.3% to 60.0%. Based on 42 of the 128 cases with a single known contact with a SARS case, the mean incubation period was 5 days (range 2 to 10 days). INTERPRETATION: Evidence to date suggests that SARS is a severe respiratory illness spread mainly by respiratory droplets. There has been no evidence of further transmission within the hospital after the elapse of 2 full incubation periods (20 days).
BACKGROUND: Severe acute respiratory syndrome (SARS) was introduced into Canada by a visitor to Hong Kong who returned to Toronto on Feb. 23, 2003. Transmission to a family member who was later admitted to a community hospital in Toronto led to a large nosocomial outbreak. In this report we summarize the preliminary results of the epidemiological investigation into the transmission of SARS between 128 cases associated with this hospital outbreak. METHODS: We collected epidemiologic data on 128 probable and suspect cases of SARS associated with the hospital outbreak, including those who became infected in hospital and the next generation of illness arising among their contacts. Incubation periods were calculated based on cases with a single known exposure. Transmission chains from the index family to hospital contacts and within the hospital were mapped. Attack rates were calculated for nurses in 3 hospital wards where transmission occurred. RESULTS: The cases ranged in age from 21 months to 86 years; 60.2% were female. Seventeen deaths were reported (case-fatality rate 13.3%). Of the identified cases, 36.7% were hospital staff. Other cases were household or social contacts of SARS cases (29.6%), hospital patients (14.1%), visitors (14.1%) or other health care workers (5.5%). Of the 128 cases, 120 (93.8%) had documented contact with a SARS case or with a ward where there was a known SARS case. The remaining 8 cases without documented exposure are believed to have had exposure to an unidentified case and remain under investigation. The attack rates among nurses who worked in the emergency department, intensive care unit and coronary care unit ranged from 10.3% to 60.0%. Based on 42 of the 128 cases with a single known contact with a SARS case, the mean incubation period was 5 days (range 2 to 10 days). INTERPRETATION: Evidence to date suggests that SARS is a severe respiratory illness spread mainly by respiratory droplets. There has been no evidence of further transmission within the hospital after the elapse of 2 full incubation periods (20 days).
Authors: Christian Drosten; Stephan Günther; Wolfgang Preiser; Sylvie van der Werf; Hans-Reinhard Brodt; Stephan Becker; Holger Rabenau; Marcus Panning; Larissa Kolesnikova; Ron A M Fouchier; Annemarie Berger; Ana-Maria Burguière; Jindrich Cinatl; Markus Eickmann; Nicolas Escriou; Klaus Grywna; Stefanie Kramme; Jean-Claude Manuguerra; Stefanie Müller; Volker Rickerts; Martin Stürmer; Simon Vieth; Hans-Dieter Klenk; Albert D M E Osterhaus; Herbert Schmitz; Hans Wilhelm Doerr Journal: N Engl J Med Date: 2003-04-10 Impact factor: 91.245
Authors: Nelson Lee; David Hui; Alan Wu; Paul Chan; Peter Cameron; Gavin M Joynt; Anil Ahuja; Man Yee Yung; C B Leung; K F To; S F Lui; C C Szeto; Sydney Chung; Joseph J Y Sung Journal: N Engl J Med Date: 2003-04-07 Impact factor: 91.245
Authors: Kenneth W Tsang; Pak L Ho; Gaik C Ooi; Wilson K Yee; Teresa Wang; Moira Chan-Yeung; Wah K Lam; Wing H Seto; Loretta Y Yam; Thomas M Cheung; Poon C Wong; Bing Lam; Mary S Ip; Jane Chan; Kwok Y Yuen; Kar N Lai Journal: N Engl J Med Date: 2003-03-31 Impact factor: 91.245
Authors: Susan M Poutanen; Donald E Low; Bonnie Henry; Sandy Finkelstein; David Rose; Karen Green; Raymond Tellier; Ryan Draker; Dena Adachi; Melissa Ayers; Adrienne K Chan; Danuta M Skowronski; Irving Salit; Andrew E Simor; Arthur S Slutsky; Patrick W Doyle; Mel Krajden; Martin Petric; Robert C Brunham; Allison J McGeer Journal: N Engl J Med Date: 2003-03-31 Impact factor: 91.245
Authors: J S M Peiris; S T Lai; L L M Poon; Y Guan; L Y C Yam; W Lim; J Nicholls; W K S Yee; W W Yan; M T Cheung; V C C Cheng; K H Chan; D N C Tsang; R W H Yung; T K Ng; K Y Yuen Journal: Lancet Date: 2003-04-19 Impact factor: 79.321
Authors: Ron A M Fouchier; Thijs Kuiken; Martin Schutten; Geert van Amerongen; Gerard J J van Doornum; Bernadette G van den Hoogen; Malik Peiris; Wilina Lim; Klaus Stöhr; Albert D M E Osterhaus Journal: Nature Date: 2003-05-15 Impact factor: 49.962
Authors: Patrick Tang; Marie Louie; Susan E Richardson; Marek Smieja; Andrew E Simor; Frances Jamieson; Margaret Fearon; Susan M Poutanen; Tony Mazzulli; Raymond Tellier; James Mahony; Mark Loeb; Astrid Petrich; Max Chernesky; Allison McGeer; Donald E Low; Elizabeth Phillips; Steven Jones; Nathalie Bastien; Yan Li; Daryl Dick; Allen Grolla; Lisa Fernando; Timothy F Booth; Bonnie Henry; Anita R Rachlis; Larissa M Matukas; David B Rose; Reena Lovinsky; Sharon Walmsley; Wayne L Gold; Sigmund Krajden Journal: CMAJ Date: 2004-01-06 Impact factor: 8.262
Authors: Roy M Anderson; Christophe Fraser; Azra C Ghani; Christl A Donnelly; Steven Riley; Neil M Ferguson; Gabriel M Leung; T H Lam; Anthony J Hedley Journal: Philos Trans R Soc Lond B Biol Sci Date: 2004-07-29 Impact factor: 6.237
Authors: Annalee Yassi; David Moore; J Mark Fitzgerald; Philip Bigelow; Chun-Yip Hon; Elizabeth Bryce Journal: J Occup Environ Med Date: 2005-01 Impact factor: 2.162