Further to my letter "Suspected SARS case in Singapore" on 9 September 2003, I would like to provide you with an update. In the afternoon on 9 September, the Ministry of Health, Singapore reported a probable SARS case involving a 27-year-old laboratory worker. The man had onset of fever on 26 August 2003 around midnight. On admission to hospital on 3 September, he had fever, muscle aches and joint pain, and he developed dry cough after admission. Three serial chest x-rays were all normal. Polymerase chain reaction (PCR) tests and serology test results were positive for SARS coronavirus on 8 September. A repeat of his PCR tests in another laboratory on 9 September was also positive. Fever had subsided and the patient remains well. His close contacts have been put under home quarantine order. No other laboratory co-workers have fever or feel unwell.

The clinical picture does not meet the World Health Organization clinical case definition of SARS but there is laboratory evidence of SARS coronavirus infection. According to the Ministry of Health, Singapore, the patient has no history of travel to previously SARS-affected areas and no known contact with SARS patients, and this appears to be a single, isolated case. Investigation into the source of infection is underway.

In view of the Singaporean experience, besides the health care professionals, the Department of Health has also alerted the private hospitals and the laboratories of Hospital Authority, the University of Hong Kong and the Chinese University of Hong Kong to the incident and reminded them to maintain vigilance in infection control and disease reporting. In Hong Kong, surveillance and preventive measures against SARS have been kept in place. Stringent health screening measures at border control points are on-going. Since 9 September, the Department of Health has been distributing Health Alert Card and information leaflet to airline passengers arriving from or departing for Singapore, and has deployed health care staff to watch out for ill persons among these passengers. We will closely monitor the situation.