A fungal infection happens when a fungus grows on or inside the body and causes harm. Fungi are everywhere — in the air, soil, and even on our own skin. Most of the time, they are harmless. However, when conditions are right, they can cause a range of infections, from minor skin rashes to serious illness. This article explains the main types of fungal infections, what symptoms to watch for, and how they are treated in Canada.
What Is a Fungal Infection?
Fungi are tiny organisms that are neither plants nor animals. Some fungi are made of many cells (called dermatophytes), while others are single-celled (called yeasts). Both types can cause fungal infections in humans.
Fungal infections range from mild to serious. A mild infection might only affect the outer layer of your skin. A severe infection can spread deep into organs like the lungs, brain, liver, or kidneys. Fortunately, most Canadians only ever deal with the mild, surface-level kind.
Fungi can enter the body from the outside environment — through the skin, air, or a cut. In some cases, fungi already living on your body can overgrow and cause infection. This is common with Candida, a yeast that naturally lives in the body.
How Fungal Infections Are Classified
Doctors classify fungal infections based on how deep they go into the body’s tissues. There are four main groups: superficial, cutaneous (skin-level), subcutaneous (under the skin), and systemic (deep inside the body).
Superficial Fungal Infections
Superficial fungal infections affect only the very outer layer of the skin or hair. They are usually not painful and are the easiest to treat. Common examples include:
Tinea versicolor (pityriasis versicolor): Caused by Malassezia furfur, this infection creates lighter or darker patches on the neck, shoulders, chest, and back. It is very common and easy to treat with antifungal creams.
Tinea nigra: This appears as a brown-to-black stain on the palm of the hand or sole of the foot. It is rare in Canada but occasionally seen in people who have recently travelled to tropical regions.
Piedra: An infection of the hair shaft. Black piedra creates hard, dark nodules on the hair. White piedra creates soft, beige nodules. Both are uncommon in Canada.
Cutaneous (Skin) Fungal Infections
Cutaneous fungal infections go a little deeper, affecting the outer layers of the skin, nails, and hair. These are the most common fungal infections seen by family doctors and walk-in clinics across Canada.
This group includes infections caused by dermatophytes (a type of fungus) and by Candida yeast. Dermatophyte infections are grouped under the name “tinea,” followed by the body part affected.
Common Types of Fungal Skin Infections
There are several well-known fungal infections that affect the skin. Each one has its own name, location, and set of symptoms. Here is a breakdown of the most common ones Canadians encounter.
Athlete’s Foot (Tinea Pedis)
Athlete’s foot is one of the most common fungal infections in Canada. It affects the skin between the toes and on the soles of the feet. There are three main forms:
Erosive form: Red, itchy blisters appear between the toes (usually between the third and fourth, or fourth and fifth toes). The skin may turn white and peel, then crack and become raw.
Blistering form: Small fluid-filled blisters appear on the sole of the foot and at the base of the toes. This form is more common in autumn.
Thickened skin form: The skin on the heel becomes thick, dry, and cracked. This form can be painful and is often mistaken for dry skin.
Athlete’s foot spreads easily in wet, warm places — like swimming pools, gym showers, and locker rooms. Wearing flip-flops in these areas is one of the best ways to protect yourself.
Nail Fungus (Tinea Unguium / Onychomycosis)
Nail fungus most often affects the big toenail. It starts as a whitish area near the tip of the nail, then slowly spreads to cover the whole nail. The nail becomes thick, brittle, and crumbly over time.
Nail fungus is stubborn and takes a long time to treat — often several months. In addition, it can come back after treatment. Your family doctor or a walk-in clinic can confirm the diagnosis and recommend the right antifungal treatment, which may include oral medication.
Ringworm (Tinea Corporis)
Despite its name, ringworm has nothing to do with worms. It is a fungal infection of the skin on the body — including the chest, abdomen, and limbs. It appears as a round or oval red patch with a raised, scaly edge. The centre may look normal or slightly darker. The ring shape is what gives it its name.
Ringworm spreads easily through skin-to-skin contact or by touching contaminated surfaces. It is common in children and athletes who play contact sports.
Jock Itch (Tinea Cruris)
Jock itch affects the groin area and inner thighs. It appears as a red, scaly rash with a clear border. It is intensely itchy and more common in men, as well as in people with diabetes. Furthermore, it tends to flare up in hot, humid weather or after sweating heavily.
Keeping the area clean and dry is an important part of both treatment and prevention. Antifungal creams available at Canadian pharmacies are usually effective for mild cases.
Scalp Ringworm (Tinea Capitis)
Tinea capitis affects the scalp and hair shafts. It causes patches of dry, white, flaky skin around broken hair stubs. The hair in the affected area may break off close to the scalp, causing patchy hair loss. This condition is most common in children.
Unlike other tinea infections, scalp ringworm usually requires oral antifungal medication — not just a cream. A family doctor or paediatrician can prescribe the right treatment.
Hand Fungus (Tinea Manuum)
Hand fungus typically affects only one hand. The skin becomes thickened and scaly, or small blisters may appear. It is often found alongside athlete’s foot and nail fungus. Therefore, treating all affected areas at the same time is important to avoid re-infection.
Who Is Most at Risk?
Anyone can get a fungal infection, but some people are more likely to develop one. Risk factors include:
A weakened immune system (for example, due to HIV/AIDS, cancer treatment, or organ transplant medications)
Diabetes
Taking antibiotics for a long period of time
Living in warm, humid conditions or sweating heavily
Walking barefoot in public showers or pool areas
Wearing tight, non-breathable clothing or footwear
Being a child (for scalp infections) or an older adult (for nail infections)
People with compromised immune systems face a higher risk of invasive fungal infections — those that spread deep into the organs. These are harder to diagnose early and more difficult to treat. Health Canada provides guidance for Canadians with underlying health conditions who may be at higher risk.
How Is a Fungal Infection Diagnosed?
Your doctor will usually start with a visual exam of the affected area. However, for a confirmed diagnosis, they may use one or more of the following tests:
Direct microscopy: A small scraping of skin, nail, or hair is treated with a solution and examined under a microscope. The lab technician looks for fungal spores and threads (called hyphae or filaments).
Wood’s lamp exam: A special ultraviolet light is shone on the skin. Some fungal infections glow with a characteristic colour under this light.
Fungal culture: The sample is placed in a special growth medium to identify the exact type of fungus. Results can take one to three weeks.
As a result of these tests, your doctor can confirm whether you have a fungal infection and which type — so you get the right treatment. According to the Mayo Clinic, most superficial fungal infections respond well to antifungal treatment when caught early.
Treatment Options for Fungal Infections
Treatment depends on the type and severity of the fungal infection. Your doctor will choose between topical (applied to the skin) and systemic (taken by mouth) antifungal treatments.
Topical Antifungal Treatment
For most mild skin fungal infections, a topical antifungal cream, gel, or lotion is all that is needed. These are applied directly to the affected area, usually twice a day for at least four weeks. Many options are available over the counter at Canadian pharmacies without a prescription.
It is important to continue using the cream for the full recommended time — even if the skin looks better sooner. Stopping too early can allow the infection to come back.
Oral Antifungal Medication
Some fungal infections require prescription pills. Oral antifungals are necessary when:
The infection affects the hair or scalp (such as tinea capitis)
The infection affects the nails (onychomycosis)
The rash covers a large area of the body
Topical treatment has not worked
Oral antifungal medications are available through a prescription from your family doctor or a walk-in clinic. Some provincial drug plans in Canada may cover part of the cost — check with your provincial health authority or pharmacist. Healthline provides a helpful overview of antifungal medication options that your doctor may discuss with you.
When to See a Doctor
Many mild fungal infections can be treated with over-the-counter products. However, you should visit your family doctor or a walk-in clinic if:
The infection does not improve after two weeks of over-the-counter treatment
The rash is spreading or getting worse
The affected area becomes swollen, warm, or painful — this may signal a secondary bacterial infection
You have a fever along with skin symptoms
You have a weakened immune system or diabetes
The infection affects a child’s scalp or nails
You are unsure whether the rash is a fungal infection or something else
Early treatment leads to faster recovery and lowers the chance of spreading the infection to others. If you do not have a family doctor, most walk-in clinics in Canada can assess and treat common fungal infections. Always speak with a healthcare provider before starting any new medication, including over-the-counter antifungals.
Frequently Asked Questions About Fungal Infections
What are the most common signs of a fungal infection on the skin?
The most common signs of a fungal infection on the skin include redness, itching, scaling, and a ring-shaped or patchy rash. Blisters or thickened, cracked skin may also appear, depending on the type of infection. If you notice these symptoms, a walk-in clinic or family doctor can confirm the diagnosis.
Can a fungal infection go away on its own?
Mild fungal infections sometimes improve on their own, but most do not clear up without treatment. Without antifungal medication, a fungal infection can spread or become more severe. It is best to start treatment early with an over-the-counter antifungal cream or to see a doctor.
Are fungal infections contagious?
Yes, many fungal infections are contagious and spread through direct skin contact or by touching shared surfaces like towels, gym equipment, or shower floors. Ringworm and athlete’s foot, for example, spread easily in households and public spaces. Avoiding shared personal items and wearing footwear in wet public areas can reduce your risk.
How long does it take to treat a fungal infection?
Treatment time depends on the type and location of the fungal infection. Skin infections often clear up within two to four weeks with a topical antifungal cream. Nail and scalp infections take much longer — sometimes three to six months — and usually require oral medication prescribed by a doctor.
Is nail fungus the same as athlete’s foot?
Nail fungus and athlete’s foot are different conditions, but they are often caused by the same types of fungi. Athlete’s foot affects the skin on the feet, while nail fungus affects the nails themselves. In addition, having untreated athlete’s foot can increase your risk of developing a nail fungal infection over time.
Can people with diabetes get fungal infections more easily?
Yes, people with diabetes are more prone to fungal infections because high blood sugar levels create an environment where fungi thrive. Their immune systems may also be less effective at fighting off infections. Canadians with diabetes should monitor their skin regularly and speak with their doctor at the first sign of a rash or skin change.
