Good question. I honestly don’t know. The vast majority of these events are ones in which STI transmission could not occur because there is no skin contact or fluid exchange. At the events where transmission could occur I’d guess that those attendees are more knowledgeable about risks and prevention than the average population. And there’s the safer sex elevator speech before contact: http://reidaboutsex.com/safer-sex-elevator-speech-with-examp...