Nail fungus thrives best in a warm and humid environment. That is why the toenails are usually affected and rarely the fingernails.
Traces of fungi can be transferred between people or from animals to people. These spores are very resistant. They can survive for weeks on towels, bath mats, wooden slats and other floors, and remain contagious to humans.
As a rule, the infection is contracted in public baths, saunas, fitness studios or showers and especially in sports changing rooms.
Important factors in the development of nail fungus are, for example, the moisture in the shoes due to increased perspiration (especially in sports shoes), circulatory problems in diabetics or due to thrombosis. The physical pressure caused by dense shoes reduces the defensive power of the skin and nails and thereby increases the risk of infection.
In the US about 7-10% of the population has some form of nail fungus, in the Netherlands the figure is higher than 12%.
In most cases, both the nail and the nail bed are affected. As a rule, this means yellow / brown discoloration of the nail bed and the underside of the nail itself, together with a thickening of the nail and often crumbly nails. If it is a filamentous fungal infection, the discoloration starts below the tip of the nail. A yeast infection starts in the skin around the nails. An infected nail surface is characterized by white spots on a brown or gray surface.
The diagnosis can usually be made with the naked eye. If an infection is suspected but not visible, the nail can be stained and studied under a microscope, making the fungus visible. With a sample of the nail one can cultivate a fungal culture with which the fungal type can be identified.
The fungal nail can be treated in different ways:
There is special anti-fungal varnish or ointment with anti-fungal ingredients. This usually only works if the infection is in the tip of the nail, is only effective on 50% of the nail and the nail matrix is not treated. The active ingredients are ciclopirox 8% (Batrafen) and Amorolfin 5% (Loceryl Nail Polish).
If the nail bed itself is affected, or more than half of the nail, or multiple nails, a systemic drug (oral tablets, for example Lamisil) can be used against the fungus. This medicine fights the fungus from within. Tablets should be taken throughout the course of treatment until the affected nail has completely grown. There must be no interruption of treatment. This treatment usually lasts 6 months for fingernails, and 12 months for toenails. In severe cases, such as when the large toenail is affected, or in older patients, the treatment can even last 18 months or more.
Due to the expected side effects (vomiting, diarrhea, dizziness, headache, liver damage, nausea, drowsiness, hallucinations, ..) only 20-25% of infected people choose to use the antimycotic tablets. The success rate of the tablets is approximately 50%. After successful treatment, the chance of reinfection is up to 50% in the next 5 years.