Breaking Danger by Lisa Marie Rice

The dead are everywhere. The cure is in their hands. Time is running out.
In a world ravaged by a deadly plague that turns people into monsters, Haven is the last safe refuge. But the only antidote lies with Dr. Sophie Daniels, a brilliant virologist trapped behind enemy lines.

Elite ex-Ghost Ops soldier Jon Ryan is sent on a desperate mission to bring Sophie, and her life-saving vaccine, home. Battling their way through monster-infested badlands, Jon will risk everything to keep her alive.
Survival means trusting each other with their lives – and their hearts. And in the fight to save humanity, love might be their strongest weapon.
This is a previously published title.