Auto-toxic memes are any self-damaging memes for the hosts.
Highly auto-toxic memes are usually self-limiting because they promote the destruction of their hosts (such as the Jim Jones meme; any military indoctrination meme-complex; any "martyrdom" meme). (GMG) (See exo-toxic.)
It could be all memes have some spillover effect, and are all social contagions by their very nature.
Highly auto-toxic memes are self-limiting if they promote the destruction of their hosts at a greater rate than they propagate from host to host. Suicide cult memes are good examples, especially where the entire cult wipes itself out at a particular time.
Certain types of military indoctrination and 'martyrdom' meme-complexes can become auto-toxic, although in many cases the meme can spread despite the death of the host(s), and may in fact increase in strength after the host's death.