艾滋病最初被发现,是由于医生首先注意到艾滋病患者染上的寄生虫病。1979～1980年期间,在美国洛杉矶等大城市,出现了一些男性同性恶者患有卡氏肺孢子虫病和卡波氏肉瘤。这两种疾病在健康人中是很少见到的。此种情况引起了某些医生的注意,继而他们又发现这些患者有免疫缺陷的表现。对于这些当时尚不能解释的病症。他们称之为“获得性 AIDS was first discovered because the doctor first noticed the parasitic disease contracted by AIDS patients. Between 1979 and 1980, some male homosexuals in the United States, such as Los Angeles, suffered from Pneumocystis carinii and Kaposi’s sarcoma. These two diseases are rare in healthy people. This situation has drawn the attention of some physicians, who subsequently found that they were immunodeficient. For these can not explain the symptoms at the time. They call it "acquired