Nail infections may be caused by fungi, bacteria, or viruses, the most common of these are nail fungal infections. These happen when fungus gets inside the nail and through small cracks in it as well as in the surrounding skin. This nail fungal infection is known as onychomycosis. Nail infections are more common in older adults compared to children.
Different types of fungi may affect the toenails. The most common of these is a group of fungi known as dermatophytes. This condition may also be caused by yeasts or molds. The fungus may infect an injured or broken nail. The fungus may also spread from the surrounding skin to the nail itself. Toenail fungal infections may be picked up by walking barefoot in public areas that are often damp like pools, changing rooms, showers, and pools. In this kind of environment, it is easy for the fungal infection to spread from one person to another.