◘ Poor Hygiene
The mucous membrane that lines the insides of the nose keeps the nose moist. Since bacteria flourish in a moist environment, bacterial overgrowth could occur in the nose. The presence of pathogens such as bacteria or viruses could lead to infections, which in turn, could cause sores. If a person touches his/her nose or the nostrils with fingertips, without cleaning his/her hands, germs or dirt that may be present in the nails might enter the nose.