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In June 1981 in the USA, the first cases of the new illness were described. It was called the Syndrome of Acquired Immune Deficiency (AIDS). In English, it is called AIDS, in French, Spanish and Portuguese-SIDA, in Russian-SPID.
AIDS is a viral disease, damaging the human immune system. It is believed that the first case of this disease was in 1972 in Zaire. In 1977, also in Zaire a Danish doctor died, and in 1979 a Canadian nun, who had worked in Haiti for 29 years. The first notification from 1981 by the Center For Disease Control in the USA is for 5 homosexuals in Los Angeles, suffering from a rare lung infection whose cause is pneumostiskarini parasite (protozoa). This agent may be present in a healthy body without causing a disease. Its pathogenic properties occur only if the human body is with strongly impaired or suppressed immunity. The same year, New York and California reported the disease on 26 homosexuals with rare forms of skin cancer, so-called Kaposi's sarcoma. In December 1981, in England the first case of AIDS patient was registered. Soon after that, the registration of this disease was reported in other western European countries, in Canada, South Africa and Australia.
1. Causer of this disease (Etiology)
HIV, as other viruses, needs the cells it infects, so that it can be copied. These new copies of HIV cells continue to infect other cells. Thus, HIV is spreading to the billions of cells which constitute the human body. It is considered that AIDS affect lymphocytes and thus the functions of the immune system weaken. Initiallym this damage is attributed to various bacterial, fungal or parasitic agent, but the epidemiological analysis of hundreds of patients gives researchers a basis to express the idea that this disease is caused by a unknown hitherto virus.The assumption proved to be true. The first report for the isolation of HIV was done by a group of French researchers from the Pasteur Institute in Paris. This group was led by the famous virologist Luc Montagnier. Later, in 1984, the scientific team from the USA, led by Robert Gallo made a notification for a new virus isolated from ill people with AIDS. Subsequently, it appeared that the virus which French scientists isolated and this virus isolated in the USA are identical, i.e these are the same virus. It was labeled as HIV - human immunodeficiency virus. AIDS virus belongs to a large group of viruses called retroviruses. It's specific only to humans. In Central Africa, from the green monkeys has been isolated virus, which has greatresemblance to chiv-2, but does not infect humans. It is assumed that the cause of AIDS has occured throught the evolution of animal's retroviruses, acquired pathogenic properties for human. It is known that all viruses progress only in living cells. During their generation they go through several stages of development. The most important thing is reproduction of the genetic material of the virus. HIV, the famous retrovirus, penetrating and reproducing in the human organism, causes different responses from the immune system. One major type of immune response is the formation on antibodies in the blood of the infected individual. Some of these antibodies can neutralize infectious virus activity. These specific antibodies are contained in the serum of people infected with HIV.
The presence of such antibodies, when a person is infected by a HIV, should be detected by laboratory methods, which is evidence for the presence of HIV in the blood. There are many laboratory methods which allow to detect minimal amounts of antibodies against HIV, such as Ripa, Elisa's test, immunoblotting test (IF), etc.
Through these methods is that almost all patients with AIDS contain specific antibodies against HIV. It is unclear why in some people the disease may develop after weeks or months after its infection with the HIV, but in others, the incubation period may extend to 7 years and more. In others it is possible in general to don’t lead to disease. These people in whose blood the AIDS virus is found but they are not infected are called virus carriers.