The Morningstar Strain has been let loose—is there any way to stop it?

 

When there is an industrial accident some of the Morningstar Strain is actually released. The doctor who discovered the strain and her assistant will have to fight their way through Sprinters and Shamblers to save themselves, the vaccine, and the base. Then they discover that it wasn't an accident at all—somebody inside the facility did it on purpose. The war with the RSA and the infected is far from over.

This is the fourth book in Z.A. Recht's The Morningstar Strain series, written by Brad Munson.