• Once in body, HIV attacks CD4 type of White Blood Cells (WBCs) in blood and gradually kills them.

• These CD4 type of WBC helps us to fight against various infections.

• Once they are destroyed our body's resistance to fight infections goes down making one susceptible to lots of infections.

• This last stage of HIV infection is called AIDS. It takes many years for AIDS to develop and till that time an infected person usually remains healthy.