Silent Assault — Benjamin E. Miller

America's deadliest enemy is invisible...
The submarine USS Vermont is a vital part of America's nuclear deterrence arsenal. Its mission: to remain undetected and ready to launch its missiles at the first sign of a credible threat. With the Vermont poised to take action against an aggressor within her target area, the sub's location is of the utmost secrecy.

But a mysterious plague has broken out aboard the submarine. Under orders to maintain stealth, the Vermont's crew begins to die, one by one--victims of an unseen enemy waiting to seize the ship's nuclear warheads and highly classified technology.

...and about to strike
This antagonistic foreign power has further plans for the U.S., to be set in motion when the Vermont surfaces and evacuates. But a few of the Vermont's survivors have remained on board, and have plans of their own....