The Human Immunodeficiency Virus (HIV) is one of the most challenging viruses for the research and medical community in term of finding a suitable treatment for it. Till now there is not a single complete treatment for this virus. The existing drugs delay the infection or partially obstruct the spread and thus increase life expectancy of the patient.
Because of epidemic and final fate for its infection, it would be worth to coin
"Nature has introduced and using it (HIV) as a ultimate warhead to combat the human race and giving science research community an example of its complexity and a challenge by its virality"
The disease and symptoms were identified in 1981 (termed as Acquired Immunodeficiency Syndrome (AIDS) in 1982) and virus (HIV) itself was identified and characterized in 1983.
The AIDS epidemic officially began on June 5, 1981, when a report about the unusual clusters of Pneumocystis pneumonia (PCP) caused by a form of Pneumocystis carinii (now recognized as a distinct species Pneumocystis jirovecii) in five homosexual men in Los Angeles appeared in Morbidity and Mortality Weekly Report (report by Michael Gottlieb as principal author) .
It was followed by reports about the Kaposi sarcoma (a rare form of skin cancer in which reddish blisters appear on the skin, see picture) in July 1981. Over the next 18 months, more PCP clusters were discovered among otherwise healthy men in cities throughout the country, along with other opportunistic diseases (such as Kaposi's sarcoma and persistent, generalized lymphadenopathy), common in immunosuppressed patients.
In June 1982, a report of a group of cases amongst gay men in Southern California suggested that a sexually transmitted infectious agent might be the etiological agent, and the syndrome was initially termed "GRID", or gay-related immune deficiency. But soon, it was realized that nearly half of the people identified with the syndrome were not homosexual men. The same opportunistic infections were also reported among hemophiliacs, heterosexual intravenous drug users, and Haitian immigrants.
By August 1982, the disease was being referred to by its new name: Acquired Immune Deficiency Syndrome (AIDS).
Now search was for the causative agent for AIDS.
In May 1983, doctors from Dr. Luc Montagnier's team at the Pasteur Institute in France reported that they had isolated a new retrovirus from lymphoid ganglions that they believed was the cause of AIDS. The virus was later named lymphadenopathy-associated virus (LAV).
In May 1984 a team led by Robert Gallo of the National Cancer Institute, United States confirmed the discovery of the virus, but they renamed it human T lymphotropic virus type III (HTLV-III).
In January 1985 a number of more detailed reports were published concerning LAV and HTLV-III, and by March it was clear that the viruses were the same, were from the same source, and were the etiological agent of AIDS.
In May 1986, the International Committee on Taxonomy of Viruses ruled that both names should be dropped and a new name, HIV (Human Immunodeficiency Virus), be used.
Now question rose: From where this virus came?
The theory based on the resemblance to other virus is most accepted regarding the origin of HIV virus.
The HIV is very closely related to Simian Immunodeficiency Virus (SIV), a virus present in wild apes of the West African forest. The HIV strains closely resemble with strains of SIV which is known to infect chimpanzees of the species Pan troglodytes troglodytes (picture on left) or the guerillas of west south Africa. It traveled to human ( Zoonosis ) through hunting (may be either direct encounter with hunter leading to exchange of bodily fluids) or through the bush meat habit prevalent in Africa. When hunting monkeys it is not unusual for both the hunter and the hunted to exchange blood during capture. There is a large market in "bush meat" obtained from monkeys.
There are still many unresolved queries about the origin of HIV from SIV like SIV is millions of year old, then why only recently it came to human beings.
Several alternative hypotheses for the origin of AIDS have been proposed.
AIDS denialism argues that HIV or AIDS does not exist or that AIDS is not caused by HIV; some of its proponents believe that AIDS is caused by lifestyle, including sexuality or drug use. Some conspiracy theories allege that HIV was created in a bioweapons laboratory, perhaps as an agent of genocide or an accident. These hypotheses have been rejected by scientific consensus.
AIDS was officially observed in 1981. Does that infection was first time or AIDS ever existed before.
Scientist and Doctors started searching the medical back records with instances of disease /patients with similar symptoms. The earliest record of HIV / AIDS is of 1959 from a Congolese patient whose stored blood sample was analysed in 1998 and confirmed the presence of HIV.
There were few reports of patients with similar symptoms (AIDS) around 1952 but could not be confirmed of HIV presence due to unavailability of any stored sample/tissue.
The hypothetical/mathematical probability calculations state the emergence of HIV around 1930s but still require some concrete evidence regarding it.
References:
1. http://en.wikipedia.org/wiki/Origin_of_AIDS
2. http://www.avert.org/aids-timeline.htm
3. http://history.nih.gov/NIHInOwnWords/index.html and other page listed on it.
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