Should you kill mice or let them go?
Mice can get into homes and become a real problem—building nests, contaminating food, causing damage, and spreading disease. ... In other words, it's most humane to trap and kill or relocate mice as soon as possible to minimize the numbers that must be dealt with.
Is it bad to have field mice in your house?
Homeowners with field mouse infestations are at risk for food poisoning, tick-borne diseases, and other health issues. Field mice can also bring fleas and mites inside if they infest the home. The pests also chew through wires, rip up insulation, and destroy stored items in attics and garages.