AIDS caused by the Human Immuno deficiency Virus.
A group of HIV viruses called Retrovirus.
After getting into the body of the person, the virus enters into macrophages, where RNA genome of the virus replicates to form viral DNA with the help of the enzyme reverse transcriptase.
HIV enters into helper T-lymphocytes replicates and produces progeny viruses.
The progeny viruses released in the blood attack other helper T-lymphocytes.This is repeated, leading to a progressive decrease in the number of helper T-lymphocytes, the person starts suffering from infections tat could have been otherwise overcome such as those due to bacteria,especially mycobacteroium, viruses and fungi.
A widely used diagnostic test for AIDS is Enzyme Linked Immuno Sorbent Assay(ELISA)