According to MayoClinic.com, as of 2010, approximately 39.5 million people worldwide have HIV, a virus that damages the immune system. The last stage of HIV is AIDS, a chronic and life-threatening condition. HIV and AIDS patients may suffer from a variety of complications, including bacterial and viral infections, as well as cancer.
Bacterial Pneumonia
MayoClinic.com explains that bacterial pneumonia can develop on its own, or may result from upper respiratory infections such as the cold or flu. A variety of bacteria types can cause this complication.
Tuberculosis
This infection is more common in developing nations with poor resources. As MayoClinic.com explains, it is the most opportunistic infection--a type of infection that takes advantage of a weak immune system--among those with HIV, and the leading cause of death among those with AIDS. It also increases the rate at which AIDS duplicates itself in the body, increasing the rate at which the disease progresses.
Cytomegalovirus
Cytomegalovirus is a common herpes virus that is transmitted through bodily fluids such as blood, semen, urine and breast milk. Healthy immune systems are capable of fighting the virus, deactivating it so that it becomes a harmless, dormant virus in the body. In people with a weak immune system, though, the virus awakens, damaging their lungs, eyes and digestive tract; in some cases, it can cause blindness.
Human Papilloma Virus
Also known as HPV, this infection is one of the most common causes of sexually transmitted diseases. While HPV causes warts to appear on various areas of the body, it is also one of the leading causes of cervical cancer among women. HIV-positive people are more susceptible to contracting HPV, resulting in more frequent infections and recurring outbreaks of warts. For women who have both HPV and HIV, the risk of cervical cancer increases dramatically. MayoClinic.com adds that cervical cancer is more aggressive and appears more often in women who are HIV-positive.
Non-Hodgkin's Lymphoma
This is a cancer of the lymph glands that begins in the lymphocytes--white blood cells that play a vital role in the immune system and in fighting infection. Drugs.com, states that anyone with HIV may develop this cancer, though it is more likely to occur in those whose CD4 cell count is low. The CD4 cell--or T cell--is one of the cells an immune system needs to protect the body from infection. These are the cells HIV attacks, weakening the immune system. The lower the T-cell count, the more susceptible a person is to developing this cancer.
Wasting Syndrome
While aggressive treatment has reduced the cases of wasting syndrome among AIDS patients, it still affects a great number of people. MayoClinic.com defines it as a loss of at least 10 percent as a person's body weight. Diarrhea, fever and chronic weakness often accompany it.
