IS THIS YOUR BEST DEFENCE?

As Canadians anguish over how to protect themselves from severe acute respiratory syndrome (SARS), health authorities take note of what went wrong. All around Hong Kong, people go about their business in masks. The economy's losing tens of millions of dollars, commuters shun public transit and the World Health Organization (WHO), in a rare move, says stay away unless a visit is absolutely necessary. One high-rise apartment tower has been emptied, its residents quarantined in special camps built on the outskirts. The city is trying to come to grips with SARS, the mysterious ailment, likely viral in origin, that had stricken 761 people there, and 2,354 in 18 countries worldwide, by last week, killing at least 85. As labs worldwide--including Health Canada's maximum-security facility in Winnipeg (page 24)--pressed the search for the cause of SARS, the WHO maintained a global health alert, calling for any patient with atypical pneumonia to be isolated and imploring a jittery world to be watchful. In Canada, another global hot spot with more than 180 suspected and probable cases and eight deaths (with a ninth under investigation) by the end of last week, health authorities stress that the risk to the general population is extremely low. There are no non-urgent transfers of patients between health-care facilities, and in the Toronto region, elective surgeries are cancelled and some clinics closed. INSET: HOW A NEW DIESEASE STALKED THE GLOBE.