Hell & Back (Outbreak Task Force #5)
Julie Rowe

Terrorists have kidnapped her brother, and now microbiologist Ruby Toth faces a horrible choice. If she doesn't give them a vial of Small Pox as ransom, her brother will die. She knows her prickly—yet very hot—boss, Henry, could provide the help she needs. But she joined the CDC to root out insiders plotting to unleash a bio-engineered pandemic, and she can't trust anyone. Not even Henry.