"Contagion" by Katherine MacLean is a science fiction novella originally published in a magazine in the early 1950s. The story is set on the planet Minos, where a group of space explorers confronts the implications of a disease that has historically decimated previous colonies. The novella explores themes of identity, contagion, and the complex responses of human beings to new environments and situations. The narrative follows a four-member medical team aboard the spaceship "Explorer" as they arrive on Minos, believing it to be a pristine, uninhabited planet. They soon discover that a small human colony already exists, but the inhabitants have been isolated due to a deadly disease referred to as "melting sickness." The protagonists must grapple with the reality that they have been exposed to this affliction, which turns out to be a contagion linked to the genetic changes in the colonists. As events unfold, the medical team learns the disease alters their identities, leading to a crisis as they become indistinguishable from a dominant local population. The story culminates in questioning the essence of selfhood and belonging, leaving readers with thought-provoking reflections on human identity in the face of profound change. (This is an automatically generated summary.)