Ricardo's Virus by William Tenn

On the swamp-choked planet Venus, Graff Dingle has only hours to live after a stabbing leaves him infected with Ricardo's Virus, the fast-killing "yellow death" that has haunted generations of colonists. Yet even as fever and pain close in, he must track the Heatwave raiders who have stolen precious lobodin vaccine supplies and kidnapped Greta Bergenson and her father, the last hope of New Kalamazoo's survival. In the jungle, an unexpected ally appears: MacDuff, an intelligent, winged terry whose own mate has been captured for shipment to Earth. Bound by a desperate bargain, Graff and MacDuff plunge through a lawless frontier ruled by the ruthless Max Pubina, where even brontosaurus, shata, and insect swarms can kill. Using local knowledge, improvised weapons, and sheer stubbornness, Graff fights his way toward Pubina's hideout, determined to rescue his friends and reclaim the medicine before the colony is lost. In a final showdown, he storms the outlaw's house, frees the captives, and survives what should have been a fatal disease—because he and MacDuff, born on Venus, are immune to its deadly climate. This edition has been fully restored with modern typesetting, custom cover design.