Acquired Immune Deficiency Syndrome (AIDS) can be a result of two cy Virus types HIV-1 and HIV-2. A number of primate species carry similar viruses known as Simian Immunodeficiency Viruses, or SIV. Chimpanzees can carry a virus related to HIV-1, but sooty mangabeys, a type of monkey found in West Africa, can carry a virus similar to HIV-2. Humans are thought to have become infected with HIV-1 from sooty mangabeys. Baboons in Tanzania and patas monkeys in Senegal seem to have cross-infected each other's species with SIVs. A local species of green monkey carries a virus called SIVAGM, which is related to the SIVs that the baboons and patas monkeys seem to have contracted. However, the odd thing about these baboons and patas monkeys is that they are not usually infected with SIVs. A subtype of HIV-1, called subtype B, was initially found in North America and in Europe, but it is hardly ever found in sub-Saharan Africa.
             Next, HIV is usually transmitted through four different ways. The first mode of transmission is through sexual contact; this is either vaginally or anally. The second mode of transmission is through contact with infected blood, usually through a blood transfusion or through an open wound on the skin. The third mode of transmission is through shared needles; this is usually from a drug user that is infected with HIV. The fourth mode of transmission is through breast-feeding, where HIV is passed from the mother to the baby. The percentages of these modes of transmission are as follows; 75% of HIV infection is from sexual activity, 10% is passed through breast-feeding, and 10% is passed through intravenous drug use. The other 5% are passed through contact with infected blood.
             As of June 1999, about one million people in the United States have HIV, and around 45,000 more people contract HIV every year. HIV does not kill a patient, what kills a patient is infections caused by different pathogens, which then leads to ...