As of January 2014 , there has been no evidence of sustained human-to-human transmission ; however , a study group headed by one of the world ’ s leading experts on avian flu reported Reporting that several instances of human-to-human infection are suspected Suspicion .

As of January 2014 , there has been no evidence of sustained human-to-human transmission ; however , a study group headed by one of the world ’ s leading experts on avian flu reported Reporting that several instances of human-to-human infection are suspected Suspicion .