HIV哪里来的?

科学家们确定了位于中非的一种黑猩猩是人类 HIV 感染的源头。他们认为，黑猩猩版本的免疫缺陷病毒（称为类人猿免疫缺陷病毒，或 SIV）很可能是在人类为了猎取这些黑猩猩的肉而与其感染的血液接触时，传染给人类并变异成 HIV。研究表明，HIV 可能早在 19 世纪末就已从猿类传播到人类。数十年来，病毒慢慢地在非洲传播开来，随后传播到世界其他地区。我们知道，HIV 至少在 1970 年代中期至后期就已经存在于美国。

随着对 HIV 起源的研究不断深入，科学家们发现这种病毒的跨物种传播过程非常复杂。虽然黑猩猩是 HIV 的源头，但实际上有多个不同类型的 SIV 病毒在非洲的不同物种中流行，这些病毒最终通过不同的途径与人类发生接触并变异成 HIV。这一过程的确切时间仍然存在争议，但研究普遍认为，HIV 的变异与人类的狩猎行为密切相关，特别是在与猿类肉类交易和食用的过程中。

此外，尽管 HIV 从猿类到人类的跨物种传播可能发生在 1800 年代，但病毒的广泛传播则是一个渐进的过程。病毒最初主要局限于非洲的某些地区，而后随着人类的流动、城市化的加速以及国际间的交通联系，病毒逐渐传播到其他大陆。特别是随着 20 世纪 60 年代和 70 年代国际旅行的增加，HIV 在全球范围内的传播速度也大大加快。

Scientists have identified a type of chimpanzee in Central Africa as the source of HIV infection in humans. They believe that the chimpanzee version of the immunodeficiency virus (called simian immunodeficiency virus, or SIV) was most likely transmitted to humans and mutated into HIV when humans hunted these chimpanzees for meat and came into contact with their infected blood. Studies suggest that HIV may have jumped from apes to humans as far back as the late 1800s. Over the course of several decades, the virus slowly spread across Africa and eventually into other parts of the world. We know that the virus has been present in the United States since at least the mid to late 1970s.

As research into the origins of HIV deepens, scientists have found that the process of cross-species transmission is quite complex. While chimpanzees are considered the primary source of HIV, there are actually several different types of SIV viruses that circulate in different primate species in Africa. These viruses eventually came into contact with humans and mutated into HIV through various routes. The exact timeline of this transmission remains a subject of debate, but it is widely believed that the spread of HIV is closely linked to human hunting practices, especially in the trade and consumption of primate meat.

Moreover, while the cross-species transmission of HIV from apes to humans may have occurred as early as the late 1800s, the widespread transmission of the virus was a gradual process. Initially confined to specific areas in Africa, the virus later spread as human mobility, urbanization, and international travel increased. In particular, with the rise of international travel during the 1960s and 1970s, HIV spread more rapidly across the globe.