Following the tragic events in Orlando earlier this month, there were many reports of gay men being turned away when they went to donate blood. Why do non-celibate gay men have their blood donations rejected? Turns out, it's an outdated guideline from the early days of HIV AIDS. This week, Aaron looks at the FDA's guidelines for blood donation, and the modern tools we have to screen blood. John Green -- Executive Producer Stan Muller -- Director, Producer Aaron Carroll -- Writer Mark Olsen -- Graphics http://www.twitter.com/aaronecarroll http://www.twitter.com/crashcoursestan http://www.twitter.com/johngreen http://www.twitter.com/olsenvideo And the housekeeping: 1) You can support Healthcare Triage on Patreon: http://vid.io/xqXr Every little bit helps make the show better! 2) Check out our Facebook page: http://goo.gl/LnOq5z 3) We still have merchandise available at http://www.hctmerch.com