HIV infection is a disease caused by the human immunodeficiency virus (HIV). The condition gradually destroys the immune system, which makes it harder for the body to fight infections. Most people infected with HIV eventually develop AIDS. These individuals mostly die from opportunistic infections or malignancies associated with the progressive failure of the immune system. HIV progresses to AIDS at a variable rate affected by viral, host, and environmental factors; HIV-specific treatment delays this process. Most will progress to AIDS within 10 years of HIV infection: some will have progressed much sooner, and some will take much longer. Treatment with anti-retrovirals increases the life expectancy of people infected with HIV. Even after HIV has progressed to diagnosable AIDS, the average survival time with antiretroviral therapy was estimated to be more than 5 years as of 2005. Without antiretroviral therapy, someone who has AIDS typically dies within a year.
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome (AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV). This condition progressively reduces the effectiveness of the immune system and leaves individuals susceptible to opportunistic infections and tumors. HIV is transmitted through direct contact of a mucous membrane or the bloodstream with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid, and breast milk. When HIV infection becomes advanced it often is referred to as AIDS. It generally occurs when the CD4 count is below 200/mL and is characterized by the appearance of opportunistic infections. These are infections that take advantage of a weakened immune system and include: • Pneumocystis carinii pneumonia
• Extreme weight loss and wasting; exacerbated by diarrhea which can be experienced in up to 90% of HIV patients worldwide • Meningitis and other brain infections
• Fungal infections
• Malignancies such as lymphoma, cervical cancer, and
• Kaposi's Sarcoma
Today we know that Acquired Immune Deficiency Syndrome (AIDS) is a disease and not a syndrome. A syndrome is commonly used to refer to collections of symptoms that do not have an easily identifiable cause. This name was more appropriate 13 years ago, when doctors were only aware of the late stages of the disease and did not fully understand its mechanisms. A more current name for the condition, regardless of an AIDS diagnosis, is HIV Disease. This name is more accurate because it refers to the pathogen that causes AIDS and encompasses all the condition’s stages, from infection to the deterioration of the immune system and the onset of opportunistic diseases. However, AIDS is still the name that most people use to refer to the immune deficiency caused by HIV. • Acquired — because it is a condition that has to be contracted. It cannot be inherited or transmitted through the genes. • Immune — because it affects the body’s immune system, the part of the body that fights off diseases. • Deficiency — because it makes the immune system stop working properly. • Syndrome — because people with AIDS experience a number of different symptoms and opportunistic diseases.
Four stages of HIV infection:
1. Incubation Period
In the majority of the infected population, HIV remains asymptomatic for years. The only way to know if you have HIV is to be tested. It is important to know, however, that it may take up to six months after exposure to the HIV virus before you will test positive on an HIV antibody test, although most infected people will test positive within 3 months. A negative test, therefore, isn't a reliable indicator of your infection status if you were only exposed last week. Tests that look directly for HIV RNA, the virus' genetic material, can detect an...