Will humankind’s compulsion toward progress ultimately destroy the world? Science’s unintended consequences have been fodder for novelists at least since Mary Shelley dreamed up Frankenstein’s monster. Three new works of science fiction use this anxiety as a jumping-off point:

The Cusanus Game (Tor; $25.99), by Wolfgang Jeschke, translated from German by Ross Benjamin, shows us a botanist living in a not-too-distant future Rome that is under siege by nature and man. A nuclear disaster in Germany has left swaths of Europe uninhabitable, while the brutal effects of climate change and various brands of violent social unrest have further transformed the world. The botanist, a young woman named Domenica Ligrina, is one of several scientists recruited by the Vatican for a secret mission. Even before ­Jeschke reveals what extraordinary work Ligrina will be asked to do, he hints at the possibility of alternate realities. This author clearly relishes the creation of “what if?” scenarios, and he uses different characters to consider the idea of the multiverse. One such character posits that “every human being is a universe.” Another fears bending over to tie his shoe because “every decision made brings into being a new universe — whole, complete. A universe with untied shoelaces and one with tied shoelaces.” Do we have doppelgangers living parallel but distinct existences whose pain we can sometimes feel? Can time travel erase our worst mistakes without creating terrible new ones? “The Cusanus Game” doesn’t answer these questions, of course, but it’s awfully entertaining to hear Jeschke ask them.

In Parasite (coming this month from Orbit, $20), Mira Grant considers the hygiene hypothesis that children need to be exposed to germs early in life to develop a robust immune system. Sally Mitchell was 20 when a car accident left her all but dead. She was saved by a worm — a genetically engineered tapeworm implanted in her gut to keep her healthy, a practice that has become commonplace by the 2020s. Despite her physical recovery, Mitchell has amnesia and must relearn everything about being a human. SymboGen, the company that makes the “Intestinal Bodyguards,” takes charge of her care. But SymboGen may be up to no good. (Is a big corporation ever up to any good in science fiction?) Meanwhile, a mysterious illness is turning people into violent zombies. Can the sickness be stopped? And what do the minds behind SymboGen have to do with it? While unevenly executed, “Parasite” offers fine food for thought — as well as one particularly entertaining figure: a garrulous psychopathic tapeworm named Tansy. Presumably, the story’s many loose ends will be tied up in the sequel next fall.

David Barnett’s Gideon Smith and the Mechanical Girl (Tor; paperback, $14.99) tells the story of an innocent abroad in a steampunk version of Victorian England. An avid reader of tales of derring-do, Gideon has grown up in a small fishing village with his gearship-captain dad. After his father’s unexplained disappearance at sea, the young man determines to find out what really happened, traveling (with Maria, a clockwork woman he meets along the way) to London, where they can see the Taj Mahal and the Lady of Liberty, a statue commemorating the failed American revolution of 1775. Eventually, the fanboy becomes an adventuring hero himself. Barnett, a British journalist, includes among his characters Bram Stoker, a haughty vampire countess, a tough-as-nails dirigible pilot and rampaging mummies. All are drawn into the heart of this fun, sometimes bawdy, romp toward the discovery of an infernal device that might destroy the world.

Sklaroff is a Washington-based writer.

”The Cusanus Game” by Wolfgang Jeschke. (Tor)