Imagine that Deuteronomy 14v8 had made it taboo to eat primates then the human race might have avoided HIV if that message had been preached in Africa. Were there religious groups in Africa who had taboos against eating primates ?
Maybe apes were uncommon in Israel so it just never occurred to eat them. However would we ever have known that we had avoided HIV ? Deut 14 would need to have said, " Do not eat apes or monkeys because a dire disease / virus might get going in humans & spread round the globe " [ 1 kings 10v22 mentions apes & baboons ]
Imagine if Hitler had started his deranged plans in the Congo in 1940, he might have killed the tribe where the first HIV occurred and inadvertently prevented the pandemic of HIV - saving more lives and suffering from HIV than the thousands he murdered.
Imagine that in 1910 a christian etc had claimed to have a word of knowledge that 3 people in Congo had a deadly new virus and was able to identify them from seeing them in a dream. Then the person was able either to convince them to be celibate or otherwise be quarantined. That would be either a fluke or indication of supernatural, but why wouldn't a god just prevent the mutation of SIV to HIV or switch off the unlucky first person ? or make them unlucky in love ?
Imagine that religion hadn't impeded science so much & that science had risen earlier so that the danger of a virus like HIV occurring could have been predicted and rules put in place to change the culture in Congo against eating primates.
Even if the world had taken more concern for preserving biodiversity & supplying the needs of the people in Congo so they weren't driven to eat chimpanzees etc. then HIV might have been prevented ?
However maybe it was well intentioned anti-malaria injection campaigns which aided HIV ? Or explaining reasons against promiscuity might have prevented the spread ? It is a mixed picture.
Religious leaders are unable to do any real good when they are like witchdoctors ignorant of the crux details of reality.