by Roger
(UK)
AIDS (acquired immune deficiency syndrome) is a state of immunodeficiency caused by the HIV infection. The immunodeficiency makes the body susceptible to many diseases, called opportunistic diseases, mainly infectious (bacterial, viral or fungal diseases) and neoplastic diseases (cancers). A person may be infected by the HIV without being under the AIDS condition, that is, he/she hasn't developed the immunodeficiency yet.