All seven people infected with bird flu in a cluster of Indonesian cases can be linked to other patients, according to disease trackers investigating possible human-to-human transmission of the H5N1 virus. A team of international experts has been unable to find animals that might have infected the people, the World Health Organization said in a statement today. In one case, a 10-year- old boy who caught the virus from his aunt may have passed it to his father, the first time officials have seen evidence of a three-person chain of infection, an agency spokeswoman said. Six of the seven people have died. Almost all of the 218 cases of H5N1 infections confirmed by the WHO since late 2003 can be traced to direct contact with sick or dead birds. Strong evidence of human-to-human transmission may prompt the global health agency to convene a panel of experts and consider raising the pandemic alert level, said Maria Cheng, an agency spokeswoman. “Considering the evidence and the size of the cluster, it’s a possibility,” Cheng said in a telephone interview. “It depends on what we’re dealing with in Indonesia. It’s an evolving situation.” The 32-year-old father in the cluster […]