Athlete's foot was first medically described in 1908. Globally, athlete's foot affects about 15% of the population. Males are more often affected than females. It occurs most frequently in older children or younger adults. Historically it is believed to have been a rare condition, that became more frequent in the 1900s due to the greater use of shoes, health clubs, war, and travel.
Fungal infection occurs when the organism invades through an opening in the nail, meaning fungi will usually attack nails that are already damaged. After infection occurs, the growth of the fungi leads to mild inflammation, which causes the nail to thicken and the nail plate to detach from the nail bed. The space underneath the nail can then serve as a reservoir for bacteria and moulds, which can cause the nail to become discoloured.
Technically called “onychomycosis”, fungal infection of the nail plate (the hard outer nail) or nail bed (that lies under the hard nail) will most often appear as yellowish, white, black or green discolouration of the nail. The infected nail may also appear thickened or brittle. In severe cases, from long-term infection (where all the tissues of the nail have been infected), the infected nail may break up and fall off.
Infected nails are usually thicker than normal and could be warped or oddly shaped. They can break easily. Nails with fungus might look yellow. Sometimes a white dot shows up on the nail and then gets bigger. When fungus builds up under your nail, it can loosen and even separate the nail from the bed. The fungus can also spread to the skin around your nail.