AIDS (aquired immunodeficiency syndrome). It is a disease in which the body's immune system breaks down and is unable to fight off infections, known as "opportunistic infections," and other illnesses tha take advantage of a weakened immune systemthis caused via virus which is named as HIV(Human
immunodefeciency virus) it is a member of a group of virus called as retrovirus. infects human cells and uses \the energy and nutrients provided by those cells to grow

(human immunodefeciency syndrome HIV ,responsible for causing AIDS )
HIV infection is generally a slowly progressive
disease in which the virus is present throughout the body at all
stages of the
disease.When this virus starts growing (that is, by reproducing itself), it
acquires the ability to
change (mutate) its own structure. This mutation
enables the virus to become resistant to previously
effective drug therapy.The goals of drug therapy are to prevent damage to
the immune system by the HIV
virus and to halt or delay the progress of the
infection to symptomatic disease.The best combination of drugs
for HIV has not yet been defined, but one of
the most important factors is that the combination be well
tolerated so that it
can be followed consistently without missing doses.
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