The Ship Avenged — S.M. Stirling

And now, the sequel...

It's ten years later, and Joat, the eleven year old techno-demon from "The Ship Avenged," is an adult herself, and by hook, crook, and blackmail (with an assist from Rand, her very own Artificial Intelligence), she's become one of the youngest commercial ship owners in human space.

Using the good ship WYAL (for While You Ain't Looking) for various motley "transport" jobs, she has quickly gained a reputation as a trustworthy courier with a flexible approach to the rules. Which is why Centrals Worlds Security haas recruited Joat and the WYAL to determine the present whereabouts of the Kolnari space raiders, with whom Joat has an old score to settle.

But Belazair of the Kolnari has his own plans for revenge through an incurable and highly infectious disease that quickly destroys the higher brain functions, leaving the body a mindless husk. Belazair needs to find a carrier ship to spread the infection - and the carrier he has hired is Joat, who is completely unaware that she is receiving a deadly cargo which could destroy civilization throughout the galaxy!