Fungal Infection Nails: Fungal infections can affect any part of the body. Fungi are normally present in and on the body alongside various bacteria. When a fungus begins to overgrow, you can get an infection.
Onychomycosis, also called tinea unguium, is a fungal infection that affects either the fingernails or toenails. Fungal infections normally develop over time, so any immediate difference in the way your nail looks or feels may be too subtle to notice at first.