WASHINGTON — When traces of H5N1 bird flu showed up in cow’s milk last year, it raised fears that the virus could become more infectious to humans. So far, that hasn’t happened, virologist Richard Webby reported April 23 at the…
WASHINGTON — When traces of H5N1 bird flu showed up in cow’s milk last year, it raised fears that the virus could become more infectious to humans. So far, that hasn’t happened, virologist Richard Webby reported April 23 at the…