Philip Hunter | Jun 29, 2003 | 7 min read
Twice yearly, World Health Organization health officials meet to strategize against influenza, a malady that kills at least 250,000 people each year. In a chess match of sorts, they work to predict their opponent's next move, in this case by modifying vaccines to compensate for changes in the critical viral antigen hemagglutinin, which triggers the host's long-term immune memory. It takes several months to manufacture and distribute flu vaccines in sufficient quantities to inoculate vulnerabl