HIV and AIDS

            
             HIV (Human Immunodeficiency Virus) is a complex retrovirus that causes AIDS (Acquired ImmunoDeficiency Syndrome). This retrovirus causes AIDS by infecting the T cells of the immune system and deteriorating it. This attack on the immune system leaves the person susceptible to life-threatening infections called opportunistic infections. There are currently two types of HIV: HIV-1 which is the strand of HIV that is chiefly responsible for causing AIDS worldwide and HIV-2 is a strand that is found mostly in West Africa. "The Joint United Nations Programme on HIV/AIDS believes that there are now over 34 million people that are infected with HIV or AIDS worldwide. In the United States there are nearly one million people have HIV or AIDS which is roughly one out of every 250 people. 40,000 Americans become newly infected with HIV each passing year. Since the beginning of the epidemic, AIDS has killed nearly 19 million people worldwide, together with some 425,000 Americans."".
             Although there is a range of theories about the origin of HIV, there is one that is believed to be true. This theory is that HIV originated from a primate SIV (Simian Immunodeficiency Virus) that then crossed over into the human population in a process known as zoonosis (zoonosis is the process in which viruses pass from animals to humans). It is believed it may have crossed over from a chimpanzee population. But this SIV is very uncommon among the chimpanzee population, thusly it is now thought that chimpanzees may have contracted it from perhaps another primate species. Although the source of the HIV-1 virus is still unknown the HIV-2 virus, has clearly been identified as originating from the sooty mangabey. The researchers from the University of Alabama have suggested that HIV could have crossed over from chimpanzees (the process in which viruses pass from animals to humans, is known as zoonosis) as a result of a human killing a chimp and eating it for food.