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Facts About AIDS As of the year 2000, nearly one million people in the U.S. were confirmed to be HIV-positive. The Centers for Disease Control and Prevention reports that 2.2 million Americans now carry the HIV virus but do not yet have symptoms. Each year, about 40,000 new HIV infections occur in the U.S. AIDS is a leading cause of death for American men and women between the ages of 25 and 44. Through June 2000, 438,795 people in the U.S. had died from AIDS (374,422 men and 64,373 women). By the end of 2000, 36.1 million people worldwide were living with HIV/AIDS, with the vast majority living in developing countries. Through 2000, 21.8 million people worldwide have died from AIDS. Between 1991 and 1996, there were more new cases of AIDS among people older than 50 than those between ages 13 and 49. Today, 11% of all new cases of AIDS in the U.S. are now in people over the age of 50. The HIV carrier rate in the U.S. is now 1 carrier for every 100 to 200 people. .
HIV is a type of virus called a retrovirus. Like all viruses, it must invade the cells of other organisms to survive and reproduce. HIV multiplies in the human immune system's CD4+ T cells and kills vast numbers of the cells it infects. The result is disease symptoms.
Nice To Know: There are two forms of HIV: HIV-1 is the more common and more potent form. This form of HIV has spread throughout the world. HIV-2, which is less potent that HIV-1, is found predominantly in West Africa. It is also more closely related to two HIV-like viruses found in monkeys. There also are different strains of the virus, which makes it difficult to find one single treatment.
About The Immune System .
Our bodies use a natural defense system to protect us from bacteria, fungi, viruses, and other microscopic invaders. This system includes general, nonspecific defenses as well as weapons custom-designed against specific health threats:.
Innate, or nonspecific, immunity is the first line of defense.