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艾滋病它被赋予的名称因为病源的原因是该疾病是不是遗传性的，但发展后，引起剂或病毒的疾病，免疫缺陷意味着该疾病的特点是削弱了免疫系统，而综合征是指一组的症状，统称为一种疾病。在这种情况下，艾滋病被认为，它涉及在某些感染和/或癌症的发展，以及在减少某些细胞在一个人的免疫系统。
每年有一个突出的病例被报道，这说明每年，这个'杀手'是暴力攻击人的生活，现在人类的生命正受到威胁。艾滋病的起源是自从生病在80年代初来到光的科学家的一个难题。但是有一项研究表明，艾滋病是由人类免疫缺陷病毒（HIV）引起的，这种病毒在上世纪40年代从动物传播到人。1959年，一个他看起来很健康的走进医院门诊，以献血为西方支持的研究某些类型的血液病在非洲中部的城市的时候。这是第一次，也是最后一次，医生谁带了他的血液再次看到他的消息是从来没有听到从再次。医生们对他的血液样本进行分析，他们将其冷冻在试管里并储存起来。但是，当时间过去了，医生们已经忘记了它。上世纪80年代中期，一些研究人员在对艾滋病的表皮进行了研究，并进行了二次调查，发现血液中含有的艾滋病病毒，导致艾滋病的病毒。因此，它被认为是最古老的标本利奥波德维尔样本的艾滋病病毒曾经分离到现在科学家认为这个标本可以帮助解决这个神秘的“背景”这一病毒。
Today, forty million people are believed to be living with the acquired immunodeficiency syndrome (AIDS) - the 3rd leading killer in the world. It is been given the name as AIDS because Acquired means that the disease is not hereditary but develops after birth from contact with a disease causing agent or virus; Immunodeficiency means that the disease is characterized by a weakening of the immune system while Syndrome will refers to a group of symptoms that collectively indicate or characterize a disease. In this case the AIDS are believed that it involved in the development of certain infections and/or cancers, as well as in reducing the number of certain cells in a person's immune system.
Each year, there are an outstanding number of cases being reported, this indicates that each year, this ‘killer’ is violently attacking people’s live; the human life now is being endanger. The origin of AIDS has been being a puzzle for the scientists ever since the illness came to light in the early in 1980s. But there is a study suggests that the AIDS is caused by the Human Immunodeficiency Virus (HIV) where this virus was transmitted from animals to human in the 1940s. In the year of 1959, a man who looked healthy walked into a hospital clinic, in order to donate his blood for a Western backed study of some type blood disease in the central African city of Leopoldville. This is the 1st and the last time for the doctor who took his blood ever seen him again as about his news was never heard from again. The doctors do analyze his blood sample; they froze it in a test tube and stored it. But when the time passed through, the doctors had forgot about it. After a quarter- century, in the mid of 1980s, some researchers were doing some research on the growing AIDS epidermis and took a second look at the blood and they discovered that the blood does contained HIV, the virus which cause AIDS. Thus, it is believe that the Leopoldville sample is the oldest specimen of the AIDS virus ever isolated and till now the scientists believe that this specimen may help in solving this mystery ‘background’ of this virus.
But how can the ‘healthy’ guy above get infected by the HIV virus? Where does this virus originate from? As mentioned early, the virus can transmitted from animal to human. This is no longer a surprise neither for the scientists nor the researchers because they have known the viral can transfer between animals and human for a long time, and this process is known as zoonosis. HIV actually is a lentivirus; it usually attacks the immune system. Lentivirus are derived from a large group of viruses which known as retroviruses. The name of ‘lentivirus’ gives the meaning of ‘slow virus’ because they usually take a long period to ‘show’ the effects against the human body. This type of viruses is common as they can be found in a numb