Doc Torr wrote:My first thought at the TWD description was malaria. The 'skeeters carry it, but do not contract it. Now, imagine something similar, where the [virus/bacteria/w/e] is carried, but not in the blood stream. When you die, for some reason, the virus crosses the barrier into the bloodstream, likely when the body becomes too weak, but before actual death. Through the blood, it moves to the neural passages and does the nasty work. The bite itself would just dump it into the bloodstream, and weaken the system as well.
Malaria is kind of funny. The mosquito actually IS the definitive host of Plasmodium
(the parasite that causes malaria), i.e. the organism in which they become sexually mature. Humans are only intermediate hosts for some development stages that are not able to reproduce sexually yet. So, in a way, humans are the vector by which mosquitos contract Plasmodium
, and malaria is just a side effect in an unimportant intermediate host, an evolutionary dead end, so to speak.
If I'm not entirely mistaken, the parasites reproduce sexually in the GI tract of the mosquito, and the (still young and asexual) offspring then moves into the salivary gland, where they linger untill the insects stings someone or something. They are injected together with the salvia (the stuff that produces the itch), go through different stages (in liver and red blood cells), reproduce asexually, untill the next mosquito stings to suck them up. So, in a way that's pretty simmilar to what you said, only what triggers the next stage of the development cycle would be the death of the host, instead of being injected into a bloodstream.
Btw., spreading of pathogens through a bloodstream is kinda difficult without working circulation. That's why I prepare for supernatural zombies instead - they are more realistic.
Off the internet until further notice.