Fungal nail infections, also known as onychomycosis, are typically caused by fungal organisms (fungi), most commonly dermatophytes, a type of fungus that thrives in warm and moist environments. Other types of fungi, such as yeast and molds, may also cause fungal nail infections. The fungi that cause nail infections usually live on the skin and can easily infect the nails if there is a break in the skin or nail bed.
Common risk factors for fungal nail infections include:
- Poor hygiene: Fungi thrive in warm and moist environments. Poor hygiene habits, such as not washing your feet regularly or wearing dirty socks and shoes, can increase your risk of developing a fungal nail infection.
- Trauma to the nail: Injury or trauma to the nail can create a space between the nail and the nail bed, allowing fungi to enter and infect the nail.
- Aging: As we age, our nails become more brittle and prone to cracking, which can create an entry point for fungi.
- Certain medical conditions: Medical conditions that affect circulation, such as diabetes, can increase the risk of developing a fungal nail infection.
- Weakened immune system: A weakened immune system can make it easier for fungi to infect the nails.
- Certain medications: Medications that suppress the immune system, such as chemotherapy drugs, can increase the risk of fungal nail infections.
- Wearing shoes that make your feet sweat heavily
- Having had athlete’s foot in the past
- Walking barefoot in damp public areas, such as swimming pools, gyms and shower rooms
- Having a minor skin or nail injury
- Having a skin condition that affects the nails, such as psoriasis
- Having a disease that causes poor circulation e.g. peripheral arterial disease (narrowed arteries reduce blood flow to the arms or legs)
- Wearing artificial nails
- Swimming in a public swimming pool
- Wearing plastic gloves for hours every day
Complications
A severe case of nail fungus can be painful and may cause permanent damage to your nails. And it may lead to other serious infections that spread beyond your feet if you have a suppressed immune system due to medication, diabetes or other conditions.
Occasionally, a bacterial infection can occur on top of a fungal nail infection and cause serious illness. This is more common in people with diabetes or other conditions that weaken the body’s defenses against infection.