What causes nail infection? (onychomycosis)

Dermatophytes are the fungi most commonly responsible for causing this condition. They are specialized organisms that live off of keratin which is the main component of nails and skin. The most common fungi that cause nail infection disease are Trichophyton rubrum, Trichophyton mentagrophytes, and Candida albicans. Everyone is at risk for infection because fungus is present everywhere in the  environment.