The human immunodeficiency virus, HIV, targets cells of the immune system in an effort to damage the cells or destroy them completely. The damage of the body's immune cells leads to a condition called immune deficiency, in which the immune system is unable to fight off disease or infection, according to the World Health Organization. The final stage, when the body is unable to protect itself from even the smallest threat, is called AIDS, acquired immunodeficiency syndrome.
History
HIV originated in chimpanzees in South Africa, according to the Centers for Disease Control. The animal form of the virus was called simian immunodeficiency virus and was contracted by humans when they hunted these chimpanzees, came into contact with their blood and ate their meat. The simian immunodeficiency virus mutated into HIV and began to spread first through Africa and then eventually throughout the world.
Transmission
HIV can be transmitted through unprotected vaginal, anal or oral sex with an infected person. Unprotected anal sex carries the highest risk of contracting the disease, according to the Centers for Disease Control. HIV can also be spread by sharing infected needles or syringes with an infected person. HIV can be passed from an infected mother to her child during pregnancy, birth or breast-feeding. Although rare, there have also been cases of contraction of HIV through a contaminated blood transfusion. HIV can't be transmitted through sweat, tears, saliva or skin to skin contact, according to the Centers for Disease Control. The virus cannot be carried through the air or water.
Symptoms
Initial infection with HIV generally causes no symptoms. However, some people experience fever, headache, swollen lymph nodes and sore throat two weeks to a month after infection, according to Mayo Clinic. As the virus progresses, an infected person will have chronic swollen lymph nodes, diarrhea, fever, weight loss and a chronic cough. These symptoms usually don't appear for almost 10 years. The final stage of HIV infection, which doesn't being until at least 10 years after initial infection, results in the acquisition of an opportunistic infection and a low white blood cell count. Once it fully progresses into AIDS, opportunistic infections, which are infections that affect those with impaired immune function, will be accompanied by night sweats, chills, dry cough, chronic diarrhea, lesions in the tongue and mouth, headaches and weight loss, according to Mayo Clinic.
Treatment
There is no cure for HIV or AIDS, but there are drugs available that can slow down the progression of the disease. These drugs are called anti-retroviral medications, and they work by interfering with the reproduction of the virus in the body, according to the World Health Organization. Treatment focuses on suppression of symptoms. The drug therapy is known as HAART, or highly active anti-retroviral therapy, and involves a combination of three or more drugs that aim to reduce the amount of virus in your body to non-detectable levels, according to Mayo Clinic.
Prognosis
If left untreated, an HIV-related health problem will generally appear within 5 to 10 years of infection. The time it takes for an HIV infection to progress into AIDS can be 10 to 15 years, sometimes longer, according to the World Health Organization. Drug therapy slows down this process dramatically.
