An HIV genetic stowaway that may have come from a related cat virus could help the AIDS virus transmit and replicate in people, U.S. researchers reported on Sunday.
Their finding, which has implications for designing new drugs or a vaccine against the fatal and incurable virus, may also shed light on how other viruses, such as swine flu, spread from animals to people, experts said.
http://abcnews.go.com/Health/wireStory?id=9264450