Bumping an old thread that I think will be helpful and reassuring to a lot of newbies around here. Check it out, there is a lot of good info in this post.
The amalgam theory is a myth. If it were true probably everybody on the planet would have BFS. My father had a mouth full of silver. he was never sick a day and lived to 86 (and he did'nt twitch) My mother is still alive at 82 (also does'nt twitch). I still stick by the unknown virus theory.