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					HIV (human immunodeficiency virus)
HIV (human immunodeficiency virus) is a virus that causes AIDS. These viruses infect
humans and can cause the immune system (immunity) of the body, so the body
becomes weak in the fight against infection. In other words, the presence of this virus in
the   body    will    cause     a     deficiency      (lack    of)   immune      system.

History
In 1983, Jean Claude Chermann and Françoise Barré-Sinoussi of France managed to
isolate HIV for the first time from a patient with lymphadenopathy syndrome. [2] At first, it
is called ALV virus (lymphadenopathy-associated virus) [3] Together with Luc
Montagnier, they prove that the virus is the cause of AIDS. [3] In early 1984, Robert
Gallo of the United States is also researching on the virus that causes AIDS, called
HTLV-III. [2] [4] After further investigation, proved that the ALV and HTLV -III is the same
virus and in 1986, a term used to refer to the virus is HIV, or more specifically called
HIV-1.                                                                                    [5]
Not long after HIV-1 is found, a new subtype is found in Portugal from patients
originating from West Africa and later called HIV-2. [2] Through cloning and sequence
analysis (genetic makeup), HIV-2 has a difference of 55% of HIV-1 and are antigenically
distinct. [2] Another major difference between the two strains (strains) of the virus is
located in the envelope glycoprotein. [2] The study further estimates that HIV-2
originated from SIV (retrovirus that infects primates) because of the similarity of
sequences and cross-reaction between antibodies against both types of the virus.
[2][Edit] ClassificationFamily tree (phylogenetic) showing the proximity of SIV and HIV.
Both species of HIV that infect humans (HIV-1 and -2) was originally derived from the
west and central Africa, moving from primates to humans in a process known as
zoonosis. [6] HIV-1 is the result of evolution of the simian immunodeficiency virus
( SIVcpz) found in a subspecies of chimpanzee, Pan troglodyte troglodyte.Meanwhile,
HIV-2 virus species is the result of evolution of different strains of SIV (SIVsmm), found
in sooty mangabey, old world monkeys Guinea-Bissau. [6] The majority of HIV infections
in the world caused by HIV-1 because the virus is more virulent species and more easily
transmitted than HIV-2. [6] Meanwhile, HIV-2 still largely confined to West Africa. [6]
Based on genetic susuanan, HIV-1 is divided into three main groups, namely M, N and
O. [7] HIV-1 Group M consisted of 16 different subtypes. [7] While in group N and O
have not been known clearly the number subtypes of the virus incorporated in it. [7]
However, both groups have a kinship with SIV from chimpanzees. [7] HIV-2 has eight
subtypes that allegedly originated from sooty mangabey different. [7]
If some of the HIV virus to infect different subtypes of the same individual, there will be
circulating recombinant forms (circulating recombinant forms - CRFs) [8] (English:
circulating recombinant form, CRF). Part of the genome of different HIV subtypes will
merge to form a new whole genome. [9] form the first recombinant recombinant AG
found is of central and western Africa, then recombinant AGI from Greece and Cyprus,
then recombinant AB from Russia and AE from southeast Asia. [9] Of all HIV infections
occurring in the world, as much as 47% of cases are caused by subtype C, 27% of
CRF02_AG, 12.3% of subtype B, subtype D was 5.3% and 3.2% is a CRF AE , while the
rest come from other subtypes and CRFs.