Plague Planet (Wandering Engineer #5)

Things just weren't looking good for John Henry Irons, Fleet Admiral of the once mighty Federation of Sapient Planets, ever since his awakening five years ago he'd been through the ringer emotionally. First, finding his beloved civilization destroyed. But he'd vowed to rebuild.
Twice in moments of seeming triumph he was cut down, kicked out or driven out of a system he was trying to help.
Now things were starting to look up, he had his own courier ship, the Phoenix, to get him around the sector. With his loyal AI crew he was fairly certain he could finally get started on laying the ground work of the new Federation.
He thought Epsilon Triangula would be just a stopping point, the place to refuel before his long jump across the sector, but once again events conspired to involve him in local affairs and his reputation and the desire of others to find people like him brought him face to face with an old and terrifying enemy.
Irons has fought many battles in his lifetime, but how can he fight something he can barely see? Something that can reproduce a thousand fold in the blink of an eye and is carried by the winds of the planet? And how will he deal with the terrified people he's trying to help?
Is he going to be forced to watch millions die on this PLAGUE PLANET?