Aids stands for Acquired Immune Deficiency Syndrome. We say that this disease is acquired because it is not an infection that is inherited. It is caused by a virus (the human immunodeficiency virus or HIV) which enters the body from outside.
Immunity refers to the body’s natural inherent ability to defend itself against infection and disease.
Immune deficiency refers to the fact that the body’s immune system has been weakened so that it can no longer defend itself against passing infections.
A syndrome is a medical term which refers to a set or collection of specific signs and symptoms that occur together and that are characteristic of a particular pathological condition.
Although we use the term ‘disease’ when we talk about Aids, Aids, strictly speaking, is not a specific illness. It is really a collection of many different conditions that manifest in the body (or specific parts of the body) because the HI virus has so weakened the body’s immune system that it can no longer fight the pathogen (or disease-causing agent) that invades the body.
It is therefore more accurate to define Aids as a syndrome of opportunistic diseases, infections and certain cancers - each or all of which has the ability to kill the infected person in the final stages of the disease.