Rampant promiscuity invites disaster (Score 2)

Anyone having 750 sexual partners over 3 years is a walking petri dish for all sorts of venereal diseases. It's no surprise that AIDS took hold in the gay community if it's true that that level of promiscuity was commonplace.

In the 1970's San Francisco had a male population of 345,680 (http://www.bayareacensus.ca.gov/counties/SanFranciscoCounty70.htm) of whom 6.2% were gay (http://time.com/3752220/lgbt-san-francisco/). That works out to a male gay population of 21432 people.

According to the CDC, the transmission rate for AIDS is about 1.4% per exposure. (http://www.cdc.gov/hiv/risk/estimates/riskbehaviors.html). Patient 0 acknowledged having 750 partners. I would imagine he had intercourse with each partner a few times (guesstimating 3 times each). The results in 750 * 3 = 2250 exposures. With a transmission rate of 1.4%, he caused an additional 31 new AIDS cases over those 3 years. Since the article itself stated that this level of sexual activity was commonplace, it's easy to see how this horrible epidemic exploded in such a short time. If you have a couple thousand very promiscuous people, and each one of those thousands of people go on to infect 31 others over a few years, it's easy to see why this happened in the way that it did.

Over the course of human existence, I suspect this pattern of behavior has been the cause of numerous epidemics. In olden times, people did not understand why new diseases emerge, but on occasion, they did correlate disease with excessive promiscuity. Thus various taboos have been established as societies sought to protect themselves. Over time, memories fade and we forget the original reason for a particular taboo, but I bet at least some taboos have a very good reason for existing.