i seen that show a few months back, its tha irakanji jellyfish, very small, something like the size of pea.
i seen the marine biologists catching them with drift nets and looking for them in the water
they both got stung by them, the girl was pretty bad for a couple weeks but the guy nearly died and was sick for a long time,several months if i remember right.
i remember him saying the pain was all over his body and past extreme.
he said he wanted to die.
they are spreading out of their native waters because of global warming and could be found in the gulf.