Last night on the Science Channel there was a show called "Super Worm" (which was on after "Super Jellyfish", which spawned an idea for another novel or perhaps a short story, but that's all for another time) about how awesome worms are. Close up footage. Worms doing the old in-out (actually more like the old in-in!), and a crazy German biologist going on about hermaphrodites (sweet, sweet hermaphrodites). Lots of information packed into an hour. Good stuff.
In France there is a parasitic worm whose host is a cricket. One interesting thing the worm does is to grow to many thousands of times the length of the cricket, without damaging any of the latter's internal organs. The worm wraps itself around the organs, essentially becoming a part of the cricket's system.
When the worm is fully mature, it does something amazing. The parasite mates in water, but the cricket is naturally disinclined to jump into the drink. So, the worm sends "instructions" to the cricket's body. These chemical instructions mimic those of the cricket's natural system, so the poor cricket finds nothing amiss with jumping into Francois's swimming pool while its faithful companion bursts out through the cricket's abdomen.
I seem to remember another parasite that does something similar to a particular species of ant.
If a relevant portion of a populace could be tricked into infesting themselves with a genetically engineered parasite (coded with THE WORD's instructions), that would absolutely eliminate the problem of disinclination to invasive surgery. At least a chapter could be devoted to the failures of this program.
Thank goodness for expanded cable!