Hostess is a science-fiction short story by Isaac Asimov.
A standalone story, it was first published in the May 1951 issue of Galaxy Science Fiction. It was later collected in 1969's Nightfall and Other Stories and 1992's Robot Dreams.
Summary[]
Rose Smollett, a research biologist, hosts Harg Tholan, an alien medical researcher from Hawkin's Planet, in her home. Her new husband, Drake, a security agent, is suspicious of the visitor. Tholan is on Earth to study "Inhibition Death," a disease causing immortals from other alien races to die of old age—a condition unique to humans. He reveals the disease has spread to other planets since interstellar travel began.
During his stay, Tholan theorizes that the disease is an ancient, intelligent parasite embedded in human DNA. It controls human behavior, inducing wanderlust, especially in newly married men, to spread itself. After Tholan confesses he has shared his findings with no one else, Drake kills him to prevent interstellar panic and a potential war against Earth.
Drake explains to Rose that the World Security Board already knew about the parasite and that it now has a symbiotic relationship with humanity, supposedly inhibiting cancer. After Drake leaves to dispose of the body, Rose realizes his story is a lie. She pieces together the truth: the parasite requires two different strains to mate, which occurs when two human carriers have a child. Drake, a carrier of one strain, married her—a carrier of the other—specifically for this purpose. His mission complete, he has now disappeared, leaving Rose alone with the horrifying knowledge.
Adaptations[]
The story was adapted for the radio series X Minus One, broadcast on December 12, 1956.