Fungi that are already present in or on your body can cause nail infections. If you have come in contact with someone else who has a fungal infection, it may have spread to you. According to the American Academy of Dermatology (AAD), fungal infections affect toenails more commonly than fingernails because your toes are usually confined to your shoes, where they’re in a warm, moist environment.
Athlete's foot is caused by a number of different fungi. These include species of Trichophyton, Epidermophyton, and Microsporum. The condition is typically acquired by coming into contact with infected skin, or fungus in the environment. Common places where the fungi can survive are around swimming pools and in locker rooms. They may also be spread from other animals. Usually diagnosis is made based on signs and symptoms; however, it can be confirmed either by culture or seeing hyphae using a microscope.
Athlete's foot occurs most often between the toes (interdigital), with the space between the fourth and fifth digits most commonly afflicted. Cases of interdigital athlete's foot caused by Trichophyton rubrum may be symptomless, it may itch, or the skin between the toes may appear red or ulcerative (scaly, flaky, with soft and white if skin has been kept wet), with or without itching. An acute ulcerative variant of interdigital athlete's foot caused by T. mentagrophytes is characterized by pain, maceration of the skin, erosions and fissuring of the skin, crusting, and an odor due to secondary bacterial infection.
For this treatment, the affected toe or finger first has to be soaked in warm water for ten minutes and then dried. After that, the urea-based cream is applied to the nail, and the nail is covered with an adhesive bandage. After 24 hours, the bandage is removed and the toe or finger is held in warm water again. The softened layer of the nail is then scraped off using a spatula, the cream is applied again and the nail is covered with a new bandage. This treatment is carried out over 14 days. Once the infected part of the nail has been scraped away completely, the skin beneath is treated for another four weeks with a bifonazole cream.
If the fungal infection has spread to the toenails, the nails must also be treated to avoid reinfection of the feet. Often, the nails are initially ignored only to find the athlete's foot keeps recurring. It is important to treat all of the visible fungus at the same time. Effective nail fungus treatment may be more intensive and require prolonged courses (three to four months) of oral antifungal medications.
Select shoes that fit right – Choosing the correct footwear is a must if you want to avoid toenail fungus. Shoes should not touch your toenails at all. Don’t jam your feet into shoes that are too big either – this will cause you to jam your toenail into the front of the shoe causing damage. According to the American Academy of Physicians, the best shoes have a wide toe box.
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You may first notice a fungal toenail infection as a small white or yellow spot on the tip of your toenail, especially the big toe. As the infection progresses, the toenail can become yellow, brittle—even crumbly—and thick and uneven-looking. In the worst fungal infections, the toenail separates from the nail bed. This is called onycholysis. As fungal infections worsen, the nail beds can be tender to the touch and quite painful. Sometimes women try to pretend the pain is “normal” and ignore it altogether.
Scratching infected areas may also spread the fungus to the fingers and under the fingernails. If not washed away soon enough, it can infect the fingers and fingernails, growing in the skin and in the nails (not just underneath). After scratching, it can be spread to wherever the person touches, including other parts of the body and to one's environment. Scratching also causes infected skin scales to fall off into one's environment, leading to further possible spread.
Use soap and water to wash your feet, and dry well, including between toes. Trim your toenails -- straight across -- to keep them shorter than the end of your toe. Make sure the tools you use are clean, too. Wash clippers and files with soap and water, then wipe with rubbing alcohol. You might be tempted to cover up discolored nails with polish, but don't. Your nail bed can't "breathe," which keeps fungus from going away.