Human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV).

HIV/AIDS can bypass the immune system and then destroy it. A person may not notice any symptoms for quite a long time or confuse them with those of common cold. As the infection progresses, it interferes more with the immune system, increasing the risk of such infections as tuberculosis and tumors that rarely affect people who have working immune systems. These late symptoms of infection are referred to as AIDS.

Today it’s hard to believe that this terrible disease has only been known for about three decades. In that time, HIV/AIDS has gone from a relatively unknown condition to a worldwide health crisis. According to the statistics, about 12% of people with AIDS don't even know they have an infection.

The virus is spread through contact with the blood, semen, pre-seminal fluid, breast milk, rectal fluids, vaginal fluids. Contrary to a common misconception, such bodily fluids as saliva and tears do not transmit HIV.

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