Well, AIDS/HIV has always had this reputation of being created by man (didn't do any research on it personally though, so this is based purely on word of mouth, I guess). So when I discovered the news it occurred to me that it's quite a big coincidence that the leading scientists die in a plane crash, especially now, that we're starting to see some people getting successfully cured of HIV.
Because it's ridiculous to think this is a conspiracy? It's a complete coincidence. On any long range flight like this you're likely to find a big bunch of people heading to some conference or other. Especially one like this that's a convenient link between Europe and Asia.
On any given flight you'd probably find a large number of X, where X = leading AIDS experts, semiconductor researchers (MH370 anyone?), football players, etc. You could fit a conspiracy theory for any plane crash.
Not sure why I'm getting downvoted above.