Acquired Immunodeficiency Syndrome in the United States: An Analysis of Cases Outside High-Incidence Groups

Abstract
From June 1, 1981-January 31, 1984, 201 cases of acquired immunodeficiency syndrome were reported involving persons who could not be classified into a group identified to be at increased risk for this syndrome. Transfusions of single-donor blood components in the 5 yr preceding diagnosis of the syndrome were recieved in 35 and 30 were sexual partners of persons belonging to a high-risk group. Information was incomplete for most remaining patients, but because many of these patients were demographically similar to populations recognized to be at increased risk for the syndrome, previously identified risk factors may have been present but not reported for some of them. A few persons who met the case definition for the syndrome probably had other reasons for their opportunistic disease and did not have acquired immunodeficiency syndrome. The slow emergence of acquired immunodeficiency syndrome in new populations is consistent with transmission mediated through sexual contact or parenteral exposure to blood.