Answer
HIV most likely entered humans first in the early 20th century through the consumption of ape meat in Africa. The HIV strand present in chimpanzees can be dated to have entered human hosts approximately around 1930.
This is known through research into the sequence relationship between strands. As a fast mutating virus HIV changes constantly. If the strain in one human is closely related to the strain in one other human and those two happened to have shared needles, the conclusion is likely that one has infected the other. The same logic can be used through scientific models on longer timestrands, comparing strands present in modern day apes. This leads to the conclusion that the first contact must have happened somewhere around 1930.
Work Step by Step
HIV most likely entered humans first in the early 20th century through the consumption of ape meat in Africa. The HIV strand present in chimpanzees can be dated to have entered human hosts approximately around 1930.
This is known through research into the sequence relationship between strands. As a fast mutating virus HIV changes constantly. If the strain in one human is closely related to the strain in one other human and those two happened to have shared needles, the conclusion is likely that one has infected the other. The same logic can be used through scientific models on longer timestrands, comparing strands present in modern day apes. This leads to the conclusion that the first contact must have happened somewhere around 1930.
