Where did STD's come from?

If two people do NOT own any STD, then they can't go past any to eachother. But there be a starting point, where did they come from, how did they start?Where did STD's come from?
Viruses and microbes evolve, the same as inhabitants and other animals evolve. All living things have evolved from simple single cell. Some organisms such as bacteria enjoy stayed simple. Viruses are so simple they ar not even a cell, and are not usually thought of as "alive".
Sex is nature's way of getting fragile DNA from one animal to another. STIs are bugs that have evolved to hold advantage of that instrument of getting from body to body. Some sexually transmissible bugs such as HIV, hepatitis B and syphilis can also pass from body to body by blood to blood or from mother to tot during or close to birth.
When a bug appears suddenly in the human population it may be because it have been evolving surrounded by another animal but has changed so that it can slickly infect and cause disease surrounded by humans. This is the case near HIV1 and HIV2, and is also the case next to many other virus such as the influenza viruses.
HIV1 originally evolved from a adjectives virus in indubitable chimpanzees called SIV. It changed to a form that can infect humans, and afterwards made the species jump, probably surrounded by the 1930s and possibly to a human hunter who was butchering a chimp infected near this new virus.
monkeys. . .
monkeys. At tiniest that's the theory at the back AIDS
Animals
Somebody did a monkey.
I heard that AIDS started when some sicko established to do a chimp and the DNA just didnt mix and you wrapping up up with a strange STD. Not sure if thats how avian flu started though..

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