I searched it and found only acute references. Not long term
damage.

But I did find this:
Ciguatera poisoning
http://www.chop.edu/consumer/jsp/div...c.jsp?id=75972

A poster came on the old boards once with this toxic fish
parasite poisoning that can lead to PN.
If you were in the area, you could have eaten fish?

Most of what I found describes local effects on only the area stung (mononeuritis) and some
autonomic reactions for the more dangerous venoms.

But in the end there is no real answer. I developed hypertension following
a severe Staph infection from a black fly bite. My doctor still thinks my early
onset hypertension was due to that serious infection.