As bird flu spreads, US concludes its vaccine doesn’t provide adequate protection

With human infections from a bird flu virus surging in China, US officials charged with preparing the country for influenza pandemics have been assessing the state of an emergency stockpile of vaccines against that strain. The conclusion: The stored H7N9 vaccine doesn’t adequately protect against a new branch of this virus family, and a new vaccine is needed. Rick Bright, who heads the Biomedical Advanced Research and Development Authority, or BARDA, said the H7N9 vaccine in the stockpile would not fend off a new family of these viruses that has emerged in China, known as the eastern or Yangtze River Delta lineage of the viruses. The conclusion comes amid a sharp rise in human H7N9 infections this winter in China. There have been 460 cases reported since last fall — a third of the 1,258 H7N9 infections diagnosed since the virus was first spotted in early 2013. In addition, the virus has...