When the HIV retrovirus enters the body, helper T cells and killer T-cells gradually become unable to recognize and fight off infections. Over years, these immune response cells, and other healthy cells are killed off, making it possible for other “opportunistic” diseases to take effect.
Most of the symptoms commonly associated with AIDS are not seen until the final stages. In stages 4 and 5, when the CD-4 cell count in very low and the viral rate is very high, the body is open to many opportunistic infections. The patient’s body becomes resistant to antibiotic therapy, and develops various types of respiratory infections such as tuberculosis and pneumonia, and skin infections and cancers such as Kaposis sarcoma.
The HIV virus is not transmitted through casual bodily contact (e.g. hugging, breathing on someone). It is passed through the blood, semen, vaginal fluid, pre-ejaculate, or breast milk. The only sure way of avoiding AIDS through sexual contact is abstention.