The Nation - News from Jan. 4, 1985

“Striking similarities” have been found between the virus believed to cause AIDS and one that infects sheep, a development that could indicate the deadly human disease originated in animals and that developing a vaccine could be difficult, scientists said in a report to be published in the journal Science. It said studies of the virus believed to cause acquired immune deficiency syndrome show that it is indistinguishable from animal disease agents called lentiviruses.