mh-17. typically attended by thousands from all over the world and among them leading hiv experts. their loss, likely to have an impact on research regarding diagnosing, treating and curing the disaster. former become become say it's awful, whavrps to so many people. >> we do this on a regular basis, have these international aids conferences. i try to go to all of them because i'm always so inspired by what other people are doing and what we can learn from them. since i left office, it's been a -- kind of a regular part of my life thinking about those people being knocked out of the skies, it's pretty tough. one of the victims, prominent dutch scientist joe blank. i first met him in 2004.