Drake

Even if it's true (which we can never know) it was unintentional and was the byproduct of trying to save lives. Two scientists were looking to crate a new Polio vaccine. One went to Eastern Europe, the other went to Africa, because they needed to test their new vaccines on populations that were largely untreated for polio. The reason they were looking for new polio vaccines is because the current one caused some deaths and they wanted to create a more safe vaccine.

Monkeys and chimps were used but only a chimps in Africa are known to carry a strain of HIV. While chimps were used curing the vaccinations it's not known whether any of them carried this strain of HIV or not and it can never be known now. One million African were vaccinated.