The Flu Hunters

It was a subtle warp in an otherwise routine day. Dr. Wilina Lim, chief virologist with the Hong Kong Department of Health, was sorting through the usual load of blood and tissue specimens sent to her laboratory from nearby hospitals, typically about 80 a day. On this particular day--Tuesday, May 20, 1997--one specimen came from Queen Elizabeth Hospital in Kowloon, at the far side of Victoria Harbor, where a three-year-old boy had been admitted with what turned out to be a fatal respiratory illness. Her lab quickly determined that the infectious agent was some type of Influenza A, one of two broad classes of flu virus that commonly affect humans. To identify the specific strain or subtype, the lab tested the sample, using reagents distributed by the World Health Organization. The test kits triggered no response.

Lim was intrigued but not terribly concerned. While she did not often receive flu viruses that resisted identification, it did happen. She retested the virus and again got no reaction. A month later, she forwarded samples to the Centers for Disease Control and Prevention in Atlanta and to England's Mill Hill, two laboratories in the top tier of a quiet but elaborate global surveillance network that tracks changes in the world's flu viruses. Almost as an afterthought, Lim sent a sample to Jan De Jong, a virologist at the Dutch National Institute of Health and the Environment who liked to collect unusual strains of influenza. She had never met De Jong, but over the years they had developed a rapport.

For more than a month, she heard nothing. Then suddenly, on Friday, Aug. 8, De Jong called. He was coming to Hong Kong. He had booked a flight that day. He would arrive Sunday. It seemed, at first, just a friendly visit--a chance, at last, to meet face to face.

Lim picked him up at the Kowloon Ramada on Monday morning. As she drove back to her laboratory, high in Hong Kong's craggy western hills, De Jong turned to her and asked mildly, "Do you have any idea what virus you sent me?"

THE HONG KONG INCIDENT

By now most of the world has heard of the "bird flu" that emerged in Hong Kong last year, infecting 18 people and killing six. One patient, a young woman, remains on a ventilator under intensive care. Although no new cases have been discovered since Dec. 28, virologists consider the emergence of this new virus one of the most significant and worrisome medical events of the day. And they don't think the danger has passed. In fact, the critical period could just now be arriving in Hong Kong. This is the start of the traditional flu season, when the new virus could, in theory, combine with ordinary human strains to create a supervirus that is both lethal and highly contagious.