Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) were unknown prior to 1982. Human immunodeficiency virus (HIV) is a systemic viral infection that weakens the body's ability to fight infection and can cause Acquired Immune Deficiency Syndrome (AIDS). AIDS is the last stage of HIV disease. The HIV virus destroys white blood cells including CD4+ T lymphocytes, or T helper cells.
The Centers for Disease Control and Prevention (CDC) estimates that 1.1 million people within the United States have HIV or AIDS. Approximately 56,000 people in the United States are newly infected with HIV each year. The CDC estimates that between 1981 and 2011, nearly 1.7 million Americans have been infected with HIV. Of these, approximately 600,000 people have died from AIDS.
Research has demonstrated that since the development of Highly Active Antiretroviral Therapy (HAART), the timeframe between HIV infection to the development of Acquired ImmunoDeficiency Syndrome (AIDS) has increased. Research indicates that the life expectancy of people with AIDS has also increased. Mortality rates also fell after HARRT from 29.4 deaths per 100 person years to 8.8 deaths per 100 person years.
Individuals with HIV under the age of 30 are living longer. These individual show higher CD4+ cell counts and have lower viral loads.
Through the use of combination antiretroviral therapy, HIV infection has become a treatable chronic disease. Research from 2006 indicates that women are the fastest growing group with HIV / AIDS diagnoses.
By 2015, 50 percent of Individuals with HIV in the United States will be age 50 or older. There are now more than 153,000 people age 55 and older living with HIV or AIDS in the United States. Data from the CDC indicates that a quarter of all people with HIV are now over 50. As this group continues to grow older, they become more vulnerable to age-related disorders such as cardiovascular disease, changes in bone mineral density, and neurocognitive impairment.
The HIV virus is transmitted through blood-to-blood contact, across infected mucous membranes, or perinatally. The most common forms of transmission are unprotected sexual contact and intravenous drug use, in which needles are shared.
Once a person is infected with the virus, the HIV replicates itself in lymphoid tissue and slowly destroys CD4 positive T-helper cells, thus weakening the immune system. A patient infected with the virus can be asymptomatic for as long as 10 to 15 years, but eventually the virus will destroy enough CD4 cells to make the infected person susceptible to infections he or she would not normally be susceptible to.
HIV/AIDS is a complex chronic disease that has many stages and symptoms.
A diagnosis of AIDS is made once a person's CD4 cells reach a count below 200 cells/mm3, or if a person contracts a condition from a list of 26 conditions defined by the Centers for Disease Control which include many opportunistic infections.
Prior to the late 1990s, persons with an AIDS diagnosis had a survival rate of approximately 2 years. Today, Highly Active Antiretroviral Therapy (HAART) has dramatically altered the survival rate of persons with HIV/AIDS in countries where such treatment is available. However, with the advent of HAART, new problems have emerged. Aside from complicated dosing regimens, HAART is thought to bring about metabolic changes, which result in abnormal fat distribution as well as cholesterol and glucose abnormalities.
Current research indicates that HAART-associated cardiometabolic risks are increasing.