Nail Fungus - Toes and Fingers


Epidemiology of toenail fungus

The occurrence of onychomycosis has been reported 23% across Europe and 20% in East Asia. In north America the statistics are found to be 14%, with fungal infections constituting the 50% of nail related diseases. Since this infection is contagious and can be transmitted directly or by using the belongings of an infected person, this serves as the reason for such wide spread rate of this infection.

Pathophysiology of toenail fungus

The pathophysiology of a disease refers to the study of changes caused by it to the suffering organ or organism. In the case of toenail and fingernail fungal infections, the pathophysiology of the nail is altered such that it is not able to provide its normal function. The nail becomes distorted, weak and the whole morphology may appear different. The function of the nail is to protect by providing a hard covering to the nail bed. In this case, the affected nail part or even the whole nail fails to do so. This results in weakening of the nail and often times the nail even gets separated from the nail bed.

What Is A Fungal Infection?

Fungus, plural fungi is a class of organisms with over 144,000 known species. Fungus holds great importance for the environment and medical sector. Fungi are considered as one of the most widely distributed organisms worldwide; Some are found free-living in soil or water; others from parasitic or symbiotic relationships with plants or animals. Some common examples of fungi include Mushroom, mildews and mold. However, not all types of fungi are harmful but some can cause severe suffering for human beings and other living organisms.

Fungal infections are common all over the world and it only occurs when an invading fungus captures over the human body and the immune system of human is too weak to combat. Fungi are populated in our environment and are found flying freely in the atmosphere, they also divide and reproduce in the tiny spores that are present in the air. These fungi that are not visible to eh naked eye can enter into the human body through our respiratory system and can land inside to form a parasitic relationship within our lungs, throat, liver or any other hospitable part of the body causing a severe infection. In some cases, fungi also attack the intestines or the genital area of the human body causing severe hazard to health however, almost all the infection caused by fungus are curable with proper care and treatment.

Sounds dangerous? It is. That is why it is so important to have a strong immune system which will prevent fungal infections to be developed in our body. Since fungi reproduce so rapidly, they are difficult to control. One of the most commonly found fungal infections are fingernail and toenail fungal infections.

This article will discuss nail infections in detail while providing a brief on how to avoid them and the treatments that could prevent them from spreading.

The ideal environment for a fungal infection to grow in warm and damp conditions. And that is the major reason most fungal infections inhabit in areas surrounding nails. Nail fungus also called onychomycosis (On-ih-koh-my-koh-cis) is a common nail condition in which the affected nail looks yellow or drained of any color. Usually, it begins with a small yellow spot which is the first indication of the infection occurring and probably the stage where care should be taken to prevent further advancement in infection. In early stages, the infection is not that even painful and does not give a constant stinging sensation however, if ignored for long while it can start bothering you and may become worse. In early stages of infection self-treatment such as keeping your fingers and toes clean can suffice and there might not be any need of proper medication or treatment to make the infection go away.

As the fungal infection starts to make its roots deeper into the toenails, the whole nail may appear yellow and thick with crumbled edges. If the infection rests for too long and is not treated properly it might come back again and again. So, to clear the air lets begin with the medical theory behind nail infections that will aid in understanding the whole psychology behind this disease.

Fungal disease is the leading cause of nail dystrophy. Fungal nail infections are a superficial fungus infection (dermatophytosis) caused by a fungus that enters below the nail into the nailbed. This could be entirely external through some mild or wet environment or an already existing fungus inside the human body which could lead to external infection. During the early stages’ onychomycosis could only be seen or felt as a cosmetic disorder, however, without any treatment the nail can become so thick and brittle that it could cause pressure, irritation and pain inside the shoes or during walking. Nail fungus makes up about 50% of nail abnormalities and according to a survey "up to 10% of all grownups in Western countries suffer from infection of the nails at least once in their life. This percentage increases to 20% of adults who are age 60 or older”.

Why does the onychomycosis fungus attack toenails and fingernails?

Even though fungal infections are not only limited to nail areas, there are other type of fungal infections as well, for example, fungal paronychia which is the inflammation of the tissue folds surrounding the nail. However, the most common areas for fungi to cause infection is still around fingernails and toenails, toenail holding the highest probability for infections, the reason behind this is easily understandable. The area surrounding our nails is prone to accumulate most of the dirt and bacteria that are not even visible to the naked eye. While we use our hands to touch everything throughout the day, from tying our shoe laces in the morning to holding doors and handles in the bus for support, then using the same hands to eat food, we don't even realize how many germs we consume in our body. Besides that, fungal infections are so easily transmittable from one person to another, while borrowing gloves from somebody else or getting a manicure/pedicure at the salon; you might think you are getting your nails cleaned which is not the case always. So, it is advised to ask for clean healthy tools every time you visit a salon, that will sound annoying and nosy but it is worth preserving your health.

On the other hand, the chances of having fungi infections around toenails are much higher because of toes being the damp and moisture containing part of our bodies for longer period of times, especially for people who wear socks and shoes for longer time periods such as students and office going people as the feet remain closed inside shoes and socks, they are more likely to sweat and the blockage of light and air serves as the perfect condition for the growth of anaerobic bacteria, thus fungi. The most common heard fungus infection, known as Athletes foot is the result of continuous moisture in the upper layer of the skin of the foot. It is also known as tinea Pedi and ringworm of the foot. The fungi causing Athletes foot, remain harmlessly on the skin until they find ideal conditions for their growth, that's when they multiply and reproduce to form a painful infection usually between the toes. Thick, tight and compact shoes are more likely to aid the growth of ringworm as they keep the feet moist and warm. This is the reason that this infection is mostly developed in athletes, as the name suggests because athletes practice sports for long hours in closed shoes. To support the reasoning; only 0.75% of people who walk barefoot or do not use tight shoes more often, are affected by this skin condition. 

Who is most likely to develop fungal infections?

Men are at a higher risk of developing fungal infections as compared to women. The reason is their poorer immunity as compared to women as the only fighting factor that prevents fungus from occurring in the immune system and women are said to have a stronger immune system than men.

Older people have more chances of developing finger and toenail infections. This is due to their poor circulation system as our antibodies are present in blood so a poorer circulation speed will result in the rate at which antibodies reach the target site to be slowed down. Besides that, our nails also grow more slowly and thicken as we age.

People suffering from diabetes develop foot infections more often. Because the healing power of people suffering from diabetes is affected drastically due to their abnormal blood sugar level. Risen sugar levels result in poor immunity thus more prone to bacterial infections.

Moreover, if you regularly wear artificial nails or apply nail polish that is shared with several people or have a nail injury the chances of bacteria attacking and causing an infection are more likely. Also, swimming in public swimming pools, visiting swampy, high moisture places and wearing closed shoes such as boots and tennis shoes and gloves will cause fingernails and toenails to develop a fungal infection.

What are the main types of toenail and fingernail fungal infections?

There are many types of fungal nail infections that develop over time and can be caused by a different class of fungi. Since the development of infection is a gradual process so a slight change in the texture or look of the nail should be considered seriously before it gets much worse. Some of the most common types of fungal infections that affect majorly the areas surrounding fingernails and toenails are listed below. All these nail infections are sub-classes of onychomycosis.

Distal subungual onychomycosis (DSO)

The most common type of fungal nail infection is DSO caused by the same fungi that are behind the Athlete's foot. It is the infection that affects the nail and the skin present under the nail, known as the nail bed. The infection originates from the nail bed and partial nail turns yellow or white, which is the first indication of DSO. In this type of infection debris, bacterial dirt, broken nail fragments and pieces of dead skin accumulate under the nail and as the condition worsen the nail could also crumble and break. DSO is a lifelong infection that can be difficult to overcome and even harder to treat. Improper care and wearing tight shoes may worsen the condition.

White superficial onychomycosis (WSO)

WSO is the second most commonly occurring nail infection. This is also relatively easier to treat as only the top surface of the nail is affected. The infection starts with the formation of white spots on the nail surface, eventually leading to the entire surface of the nail to become white and crumbly with a chalky look. However, with proper treatment and care the condition goes away with time and the nail does not separate from the skin as well.

Candida onychomycosis

Candida onychomycosis is also known as a yeast infection. This type of onychomycosis is not very common but affects the nail and the skin surrounding the nail area (nail folds). This infection is more commonly found in fingernails rather than toenails. The worst thing about this infection is that it can affect multiple nails at once causing the nail to be separated from the nail bed. The common symptoms of this type of condition include discoloration of nail or turning of a nail into yellow, brown, white or greenish with an odd shape. The nail may appear thicker than normal and the skin fold (the area surrounding nail) may look reddened, swollen and tender. Candida onychomycosis is the most painful type of infection as compared to others.

Proximal Subungual onychomycosis (PSO)

It is most commonly found in people who are HIV positive. Caused by dermatophyte this infection affects the base of the nail and skin surrounding the nail area. The skin fold becomes thick and thus resulting in the nail separating from the nail bed. The nail appears opaque while the base of the nail appears white. This is most common on foot and the top of the foot may also become affected.

The 4 types of nail infections are all caused by dermatophytes, the reason for their different names is because of their area of infection. Each infection has a different severity level from the other, occurs and spreads in a different manner, this classification makes it easy to identify thus easier to select relevant treatment method.



A badly infected toenail with fungus. Toenail fungus can present in a variety of ways. Nail fungus does not just affect the toes. A chart on the prevalence of onychomycosis. Different example of toenail fungus. 	A badly infected toenail with fungus


Before getting a medical diagnosis from a professional doctor there are some symptoms that can be checked for the possibility of infection these common symptoms are found in almost all types of finger nail and toe nail fungal infections and include:

  • Discoloration: this is the first symptom that is seen when a fungal infection is on-set. A slight discoloration of the entire nail or white or yellow spots may appear on the nail. In some cases, the whole nail turns into an ugly dark color that might seem like a blood clot too.
  • Thick and cracked: an infected nail appears clearly thickened and more fragile than before. Upon a minor contact with any surface the nail might hurt with a fear of coming off.
  • Distorted or out of shape: the irregular shape of nail may indicate a fungal infection is own its way.
  • Smelling slightly foul: nail infections are caused by bacteria and the accumulation of broken nail fragments and dead skin cells. All these combined produces a foul smell. In severe cases the nail fungus might even discharge a foul-smelling liquid which is both painful and has a clear bad smell.
  • Dermatophytids: another less common symptom of nail fungus includes fungus-free skin lesions called dermatophytids. These skin fragments appear like rashes and may be far away from the point of infection.

Diagnosis of toenail fungus

A fungal infection on toes and fingers can be easily identified by the person who is suffering. However, in some cases, people do not realize they have developed an infection and continue with their daily routine which results in worsening of the condition. The common reason for this ignorance is that in the early stages of the nail infection, it seems just like any other nail injury which would go away over time and it does not even hurt. Any abnormal changes to nails should be medically investigated.

This condition can be easily self-diagnosed, the early symptoms include yellowing or different colored spot formation on the nails. The nail may also appear more brittle than usual and might hurt upon touching or pressing. If you feel these symptoms occurring or some of them it is recommended to immediately visit a dermatologist who can further examine your condition and reach a conclusion. The doctor will ask you about symptoms and may also take a nail clipping to look at under a microscope and examine for fungal infections by running out a series of laboratory tests.

When to see a doctor?

You should immediately visit a doctor if you see symptoms of nail fungus. A dermatologist is the person specialist for helping you treat your nail fungus. Besides proper medical care and treatment, there are some alternative home remedies that will help in speeding up the recovery process and may increase the chances that infection does not return.


Causes of Fungal Infection

As the nail ages, it becomes brittle and dry. This results in nails breaking and allowing for more bacteria to enter into the nails. This is the reason why nail infections are more common in older people as compared to children even though children spend more time outdoors wearing closed shoes and socks. Factors other than the ageing of the nail that promote these infections include poor blood circulation, weak immune system and improper maintenance and cleaning of hands and feet. 

However, there are certain factors that can enhance the risk of developing nail fungus. These include:

  • Sweating heavily: People who sweat more or have smelly sweats are at a higher risk of developing nail infections. Since their closed feet and hand will stay moist and warm due to excessive sweating this will be the ideal condition for the bacteria to grow.
  • Having a history of athlete’s foot: Once a fungal infection occurs, chances are it will happen again and again over time. As bacteria multiply at a fast pace so humanly it is impossible to eradicate all the bacteria from the body even the dangerous ones, thus the only solution is to create conditions that allow the growth of bacteria to be stopped and controlled below dangerous levels.
  • Walking barefoot: If wearing closed boots serves as a greater risk for fungal infections, so as walking barefoot does. Especially in damp communal areas, such as swimming pools, beach huts, gyms and public toilets where the conditions are ideal for bacterial growth. The bacteria transfer from host to host in such conditions.
  • Skin or nail injury: An injured part of the nail or skin surrounding the nail is more likely to be invaded by the bacteria. This process is called Psoriasis. In psoriasis, the skill cells divide rapidly thus to compensate the skin injury, the sped division of cells forms extra skin cells to form a hard, patchy covering over the skin. It is a chronic disease that goes and returns often. 
  • Poor Hygiene: Probably the most common reason for recurring finger and toenails infections. Washing feet and hands help remove dirt and bacteria that accumulate over skin throughout the day. Even when our skin feels dry and clean, these bacteria might be still there and upon meeting the ideal conditions will vigorously grow and cause infection. It is also advised to use antibacterial soap twice a day to wash hands and feet. 


Treatments for nail fungus vary from the type of infection to the stage of infection and the severity of infection.  It is important to realize that toenail and fingernail fungus can be a painful infection.  Once infected, it can take weeks for a patient to completely recover.  The major reason behind this is that people underestimate how seriously to take the treatment plan and can unfortunately revert back to unhealthy behaviors and habits that can worsen the conditions.  People suffering from toenail fungus often claim that they have been taking medications as prescribed for weeks but the infection does not seem to go away.  The most common treatment methods, along with some home remedies, are listed below:

  • Anti-fungal cream:  Often doctors prescribe creams for fungal infections. It is almost an essential part of the treatment. The purpose of these creams is to form a protective layer over the fungal infection which will prohibit germs and dirt particles to gather and stick to the area of infection. This reduces the chances of infection becoming worse. And for the nail area the doctor may even recommend anti-fungal nail polish.
  • Oral anti-fungal drugs:  Taking oral anti-fungal drugs is the most effective way to treat a fungal infection. Since the best way to treat an infection is to kill the germs from within. Some commonly consumed anti-fungal drugs include terbinafine (Lamisil) and itraconazole (Sporanox). The purpose of these drugs is to encourage the growth of new nail which is free of infection gradually replacing the old nail.  But the drawback of consuming oral drugs is that they may not be completely effective for adults over the age of 65. The reason behind this is their slow metabolism. Another limitation of this drug is that the result is not visible up until the end of the complete nail growth, the procedure might take as long as 4 months to be completed.
  • Nail Removal Surgery:  It is an extremely painful process but doctors recommend it when they fear the spread of infection to other nails and surrounding area as well. Surgery can be combined with topical drug to minimize the main and enhance the rate of new nail growth. Another reason that the doctor might suggest nail removal is to treat the fungal infection on the nail bed, the area below the nail, as in the presence of nail it is impossible to directly apply the medicine to infected area.
  • Laser/light-based therapy:  This is one of the recent and major inventions in the treatment of nail fungal infections. Some people who are not willing to consume oral drugs go for laser-based nail therapy. It is more expensive than other methods but does not have side effects similar to consuming oral drugs.
  • Essential Oils:  Essential oils are packed with antibacterial, antimicrobial, antifungal and antioxidants. All these properties are ideal to kill bacteria and reduce their infections. To treat infection with essential oils it is important that the oils should be 100% organic. Some of the commonly known essential oils that are known to treat fungal infections include Eucalyptus, oregano, and tea tree essential oils. The trick is to just dab a little using a cotton swab on the infected area every day.
  • Mouthwash:  Mouthwash contains all the antifungal treatments such as thymol, menthol and eucalyptus, these ingredients can help in fighting off the fungal infection on your toe and even fingernail. A mouthwash soak is recommended once a day to speed up the curing process. However, try not to overdo the process as mouthwash contains lots of other chemicals too.
  • Apple Cider Vinegar:  Apple cider vinegar is a common ingredient of every kitchen and is effective to treat toenail and fingernail fungus. The benefit of ACV is such that it can be helpful even when taken orally or topically. To have a home-made drug with anti-fungal properties take 1/3 cup of ACV mixed with 2/3 portions of water and drink it once a day. You can also soak the infected are into ACV for 30 minutes daily.
  • Ozonized Oil:  Oils combined with the infusion of ozone gas, especially olive oil or sunflower oil, can have excellent healing properties. One study proved that almost 400 patients suffering from fungal infection observed improvement in their condition when treated with ozonized oils.
  • Olive Leaf Extract:  Olive is the most essential components of healthy salads and olive oil is said to have antioxidants properties. Applying olive oil extract to the infected part will help stimulate the immune system, quickly responding to fight the infection.



Knocking out a fungal infection can require a lot of patience and willpower, especially when your daily activities and tasks are affected by a sometimes painful bacterial infestation on your skin.  Proper care and hygiene is essential, especially with respect to any sweaty parts of your body in warm humid climates or weather.  Wash your feet and hands with antibacterial soaps.  Eat healthy foods and change your socks and gloves every day to prevent the accumulation of dirt and bacteria.  Your main goal is to keep your fingers and toes clean and dry.

Since the fungal infection never entirely leaves your body, the only proactive approach is to keep the fungal growth under control and prevent the fungus from growing back to higher levels.  In addition, be sure that the shoes you wear are of correctly sized, preferably a bit loose but not too tight, and you should avoid walking barefoot, especially on wet floors, such as bathrooms, area surrounding swimming pools and locker rooms.

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