AIDS, or Acquired Immunodeficiency Syndrome, is a human viral disease. It damages the body's immune system, and gradually takes away its ability to defend itself against infection and disease. AIDS is caused by the human immunodeficiency virus (HIV). People infected with HIV are open to infections that are harmless in healthy people, but can prove fatal in them as their immune systems are greatly weakened. HIV transmission can come through sex, blood transfusion, childbirth or breastfeeding. There is no cure for AIDS, but new drugs have been invented to help lengthen and improve the quality of life for people with AIDS.
艾滋病的全称为获得性免疫缺陷综合征（Acquired Immunodeficiency Syndrome），是一种致命的传染病。它是人类免疫缺陷病毒（HIV）造成的人体免疫系统的病变。在多数情况下，HIV缓慢地攻击并破坏人体抵抗病疫的系统（即免疫系统），使得受感染的人容易得病、并最终死亡。AIDS是HIV感染的最后阶段。艾滋病通过性接触、血液接触或母婴途径传染。目前，对于艾滋病还没有有效的治疗药物或免疫的疫苗，但是通过服药治疗可延长艾滋病人生命并可改善他们的生命质量。