Genetically engineered tapeworms that protect most of the human populace from illness, boost everyone's immune system, and even secrete designer drugs begin to change and want out of human bodies they occupy.

"The SymboGen designed tapeworms were created to relieve humanity of disease and sickness. But the implants in the majority of the world's population began attacking their hosts, turning them into a ravenous horde. Now those who do not appear to be afflicted are being gathered for quarantine as panic spreads, but Sal and her companions must discover how the tapeworms are taking over their hosts, what their eventual goal is, and how they can be stopped"--...

In 2041, Georgia Mason, held hostage by a team of CDC researchers, must find her way back to Shaun Mason, who is dealing with his own problems, such as zombie bears, mad scientists and rogue government agencies, before things get worse in her post-zombie, post-resurrection America.