The idiot blurb has it that, "As a pestilence ravages the galaxy, humanity sends Marjorie Westriding Yrarier and her family to investigate a seemingly immune planet." How a pestilence would ravage totally unrelated alien communities across an entire galaxy is the real mystery here. Another dumb plot from another author who doesn't have the first clue about biochemistry and epidemiology, and worse, who doesn't even care.