Once an area attracts a Hoarvor infestation, it is difficult to eradicate the pests. Just one window or door left open, one unconscious reveler left in the streets, or a pet not properly cared for can attract the beasts. If this happens, the first priority is to disengage the creature's proboscis as quickly as possible and treat the wound.
Hoarvors are uncannily good at locating areas of strong blood flow, and if not removed carefully can cause more damage to the victim upon removal of the feeding-bore. Wounds must be kept perfectly clean to avoid complications, and every healer knows deep puncture wounds are difficult to treat. To discourage proliferation and drive an infestation out, one must burn a mixture of viper's bite leaves and hazemoss, especially at night. Placing frost salts in a circle around a dwelling can prove helpful at deterring the creatures, as well.