“Outcasts” is episode twelve of season five of Stargate: Atlantis.
The Wraith/human hybrid Michael had previously infected people with a variant of the Hoffan drug that made infected humans deadly to any Wraith who fed upon them in “The Kindred: Part 1”.
Dr. Carson Beckett is caring for some survivors of both the virus and the ensuing Wraith attack as the Wraith tried to destroy the contamination of their food supply. The team are visiting him when the village he is in visited by Wraith who demand that the survivors be handed over to them.
Some supposed moral decisions in this one as the native villagers have to decide between their own safety and that of the people they offered shelter too, but this decisions are sometimes rather too easily solved.