Severe acute respiratory syndrome epidemic in Taiwan, 2003

In Taiwan, since the first case of severe acute respiratory syndrome (SARS) was identified on February 25, 2003, a total of 3032 cases of suspected or probable SARS were reported prior to July 5, 2003. Among these cases, 664 cases were classified as probable SARS based on the clinical case definitions and 346 had a positive result for the SARS-associated coronavirus (SARS-CoV). The epidemic in Taiwan could be divided into 2 distinct stages. In stage I (late-February to mid-April) patients had traceable contact with infected patients or travel histories to known affected areas of SARS. By contrast, patients in stage II (mid-April to June) acquired infection via intra-hospital or inter-hospital transmission. The mortality rate directly attributable to SARS during the 2 stages of the outbreak in Taiwan was 11% (37 patients). Phylogenetic analysis of sequences of SARS-CoV strains in Taiwan and other countries showed that Taiwanese strains were closely related to those isolated from patients in Hong Kong and Guangdong. The nonspecific initial symptoms and signs of the illness, the absence of reliable diagnostic tests, as well as the initial lack of strict infection control measures in hospitals and effective national control policies contributed to the island-wide spread of the SARS epidemic in Taiwan. Development of an effective strategy to prepare for future outbreaks will require the implementation of an active coordinated clinical reporting system, international collaboration to identify cases in the early stage, development of laboratory tools for early diagnosis, a robust system of prepared isolation, and adequate quarantine facilities.