Lee Jong-Wook, the World Health Organization director-general, says SARS could re-emerge and spread through Asia at any time.
He warns that vigilance is the best weapon against Severe Acute Respiratory Syndrome. He made the comments at the opening of a conference in Manila on Asia's major health problems.
SARS first emerged in southern China around November of last year, but quickly spread to about 8,500 people in more than 30 countries. It killed more than 900 patients. Hong Kong, which shares a border with China's southern Guangdong province, was one of the hardest hit cities.
The city's secretary of health, Dr. Yeoh Eng-Kiong, visited Guangdong to discuss ways to improve disease surveillance systems as the cooler weather approaches.
Many scientists have speculated that the SARS virus may replicate more easily in colder temperatures, so a fresh outbreak in southern China is possible. Dr. Yeoh told reporters that health authorities must rely on their knowledge to spot trends that could signal new SARS outbreaks.
Guangdong health official Yao Zhibin says better communication between Hong Kong and his province will start with the regular sharing of information on about 30 diseases. Mr. Yao said Hong Kong and Guangdong will exchange hospital statistics on diseases around the 15th of every month, but if a rapid outbreak emerges, information exchanges should take place on a more regular basis.
Tourism and trade between Hong Kong and Guangdong mean that diseases can easily cross the border separating the two.
In addition to SARS, the World Health Organization's five-day meeting in Manila will cover other deadly illnesses, such as tuberculosis and AIDS.