According to the UN World Health Organization (WHO), the current findings on the outbreak of Severe Acute Respiratory Syndrome (SARS) continue to indicate the infectious disease spreads from person to person through close contact, with the overwhelming majority of cases occurring in health care workers and family members who have had direct contact with patients. The number of cases without such close contact remains limited.WHO advised that travel restrictions were not needed, although persons travelling to Asia should be aware of major SARS symptoms and report promptly to a health centre should they fall ill. The infectious disease is characterized by atypical pneumonia symptoms.The vast majority of cases are presently concentrated in Hong Kong and Hanoi, where 13 of the 57 patients are showing signs of clinical improvement. Singapore is currently reporting the third-largest number of cases. All reported cases in other parts of the world are linked to travel within the past 10 days to one of these destinations.The global surveillance system coordinated by WHO is working to prevent the outbreak from becoming a global epidemic. A network of 11 laboratories in 10 countries has been established and has begun data sharing and regular reporting. Efforts are under way to expedite identification of the causative agent, improve diagnostic precision and develop a diagnostic test.