Can blue hippo tang venom kill a human?

I'd imagine only if you're allergic (due to repeated exposure). It still REALLY hurts though, trust me. I was envenomated by a 1cm one and the pain was indescribable! Took a good half an hour to be able to breathe properly again and think straight, and even then it was still really, really painful for another 2-3 hours, with a lot of swelling and redness - my entire finger swelled up twice as wide as normal, as well as tingling and numbness in my entire hand - the injury site was my ring finger tip.

However this is an extreme reaction. I work with these fish and have never seen anyone else react this way to being 'got' by one.