"Narva" was a fictitious planet in the Delta Quadrant created by the con-artists Dala, Mobar, and Zar. According to them, all of the adult settlers on Narva were killed after being exposed to toxic levels of omega radiation leaving many orphans on the planet. The con artists commonly used the story in their schemes to elicit sympathy from their marks.
When Neelix and Tom Paris first met Dala and Mobar in the Wyanti system, the two con artists were posing as clerics from a hermitic religious sect whose crops, which they intended to give to the orphans on Narva, had been infected by a blight.
Later, while Dala and Mobar were posing as Kathryn Janeway and Tuvok, they told the Telsian miners that they needed to aquire bolomite to use in omega radiation therapy for the oprhans. (VOY: "Live Fast and Prosper")