A nail fungal infection is also called onychomycosis. It becomes more common as a person grows older. It is a condition that is rarely felt by children. Onychomycosis may affect the toenails or fingernails and it may spread from one toe or fingernail to another.
Nails that are infected by a fungus often become thickened, crumbly to one’s touch, brittle, and jagged on the edges. The nails also become distorted, dull, and often with a yellow, green, or brown hue. The nail may separate from the nail bed and at times it may completely fall off. In some cases, the nail may become painful, and it may give off a foul smell.