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CEPI steps up H5N1 preparedness as outbreak in cattle persists

An outbreak of H5N1 bird flu among cattle in the United States—the first known time the virus has spread into these mammals as hosts—is raising questions about whether this highly pathogenic influenza virus could become a human epidemic threat. 

Four cases of H5N1 infection in people – all of them farm workers in close contact with cattle – have been confirmed, but there has been no known onward transmission to others.  However, the virus has adapted so there is more mammal-to-mammal transmission in multiple places in the world.  Global health security experts say the virus is not considered a current risk to the general population, but they caution that the H5N1 risk level is not static. It could change—up or down—as the virus mutates.