Documenting the SARS epidemic in mainland China

Abstract

In 2003, the world was confronted with the emergence of anew and in many cases fatal infectious disease, severe acuterespiratory syndrome (SARS). SARS was caused by a novelcoronavirus, which was provisionally termed SARS-asso-ciated coronavirus (SARS-CoV) (Drosten et al. 2003;Ksiazek et al. 2003). The earliest cases of SARS occurred inmid-November 2002 in Guangdong Province, China. SARSwas first recognised in February 2003, when cases with anatypical pneumonia of unknown cause began appearingamong hospital staff in Guangzhou, China. Within weeks,similar outbreaks occurred in Hanoi, Hong Kong, Toronto,Singapore and Taiwan. Soon thereafter, cases were beingreported from 32 countries and areas (later corrected to29). After July 2003, SARS came under control thanks toenormous efforts made by national and internationalorganisations. More than 8000 cases were reportedworldwide, with over 5000 from mainland China, makingthe country the epicentre of the outbreak (WHO 2004).During the SARS outbreak in China, epidemiologicaland clinical information were obtained in difficult cir-cumstances. The available data were only to a limitedextent analysed and reported, and mainly in Chineseliterature. There is a need for a comprehensive documen-tation of the SARS epidemic in China, accessible to theinternational scientific community. Following the epi-demic, the European Union provided research funds toincrease European preparedness for emerging infectiousdiseases, and as an important component to learn as muchas possible from the experience of the People’s Republic ofChina with regard to controlling SARS. This researchprogramme was titled SARSControl: ‘Effective andAcceptable Strategies for the Control of SARS and newemerging infections in China and Europe’. From 2005 to2008, multidisciplinary research activities were under-taken, including in-depth studies of the Chinese situation,which are now reported in this supplement.The supplement covers a wide range of studies. The firstessential step was to bring together all available epidemi-ological data in one comprehensive database, whichrequired data collection and cleaning, where necessaryreturning to original hospital records. This exerciseresulted in a database containing epidemiological infor-mation of all known 5327 SARS cases, including 343deaths, from mainland China. The first paper in thissupplement presents the database and describes the contextin which the data were originally collected (Feng et al.2009a). The following three papers exploit the databasethrough a description of, respectively, the geographicspread of SARS (Fang et al. 2009); case fatality ratio (Jiaet al. 2009); and key epidemiological parameters such asduration of onset of disease to recovery or death (Fenget al. 2009b). These first four papers are followed by twocomparative reviews. One is on the major control measurestaken by China and other SARS-affected countries andareas (Ahmad et al. 2009). The other is on serologicalconfirmation of SARS to assess possible over-reporting ofSARS patients in mainland China (Liu et al. 2009a). Next,three hospital-based papers provide, respectively, a case–control study of risk factors among healthcare workers inBeijing, including the impact of protective measures (Liuet al. 2009b); a description of clinical characteristics ofSARS patients in a hospital in Tianjin that experienced alarge outbreak (Wei et al. 2009); and an analysis of thetransmissibility of SARS and the effectiveness of controlmeasures in three major hospital outbreaks (Cooper et al.2009). Some consequences of SARS are described in thefollowing three papers: an important long-term clinicalconsequence is the high proportion of avascular osteone-crosis in SARS patients treated with corticosteroids, asdescribed in a cohort study of former SARS patients (Lvet al. 2009). The economic impact of the outbreak isdescribed in a paper analysing indicators of social andeconomic activity in Beijing, such as leisure activities,transport, and tourism (Beutels et al. 2009). A positiveconsequence of SARS is illustrated by a review of Chineseliterature describing the stark increase of papers onmodelling of infectious diseases following the outbreak,representing scientific capacity building in China (Han