A team of scientists from St. Jude Children's Research Hospital in Memphis, Tenn., have developed a vaccine against the deadly Hong Kong 'bird flu.' Dr. Robert Webster, a flu expert at St. Jude, says that H5N1 influenza does not appear to be contagious from person to person, but rather it leaps directly from species to species. But, he added, it has already mutated to infect several new bird species and could continue to mutate, and so it is imperative that they be able to move the new vaccine into human trials as quickly as possible. The H5N1 flu strain emerged in Hong Kong in 1997, taking the lives of six people and infection 18 others before the virus was traced to the open-air poultry markets and stopped by the massive slaughtering of 1.5 million chickens and other birds. A few months ago, H5N1 re-emerged, prompting Hong Kong authorities to slaughter several thousand more chickens, but the virus had already spread and killed ducks and flamingos in some city parks. Researchers point to the current SARS phenomenon as an example of how quickly and suddenly a new infectious disease can occur.