Ringworm symptoms consist of red and round spots that become increasingly larger. The rings are sharply defined and the border area is slightly raised and shows redness. Ringworm is a fungal infection of the skin characterized by a sharply defined round spot, which slowly increases in size to 10 cm in diameter or more. The skin is slightly thickened and flakes especially at the edges. The spot in the middle will eventually become somewhat lighter in color as healing occurs. Ringworm is very contagious and can be transmitted from animal to human, human to human and human to animal. Ringworm can be treated with a drug that kills fungi.
- What is ringworm?
- Cause of ringworm
- Is ringworm contagious?
- Carriership
- How does contamination occur?
- Fungus penetrates the skin
- Symptoms of ringworm in humans
- Examination and diagnosis
- Physical examination and fungal culture
- Differential diagnosis
- Treatment of ringworm
- Prognosis
- Prevention
What is ringworm?
The term ‘ringworm’ can mislead you, because it is a fungus and not a worm that causes the skin condition. Ringworm has nothing to do with worms. Ringworm is actually a descriptive term because it creates an ever-growing ring on the skin that resembles a worm. Ringworm is a highly contagious, superficial fungal infection of the skin that causes red, scaly patches in the shape of a ring. The spots are usually on the trunk and limbs (arms and legs). In medical jargon this is called ‘tinea corporis’ and ‘tinea cruris’ respectively. The spots can be quite itchy, causing you to have a tendency to scratch.
Cause of ringworm
All kinds of fungi and fungal infections occur in nature, in both humans and animals, but also in plants and food. Ringworm is caused by a fungal infection with a type of fungus that is capable of infecting human skin. The fungi grow in the outer layer of the skin, also called the stratum corneum. Fungi reproduce by means of spores. Under conditions that are favorable to them, a moist and warm environment, they can grow into fungi. A species of fungus capable of infecting human skin is called a ‘dermatophyte’. With ringworm, a pet is often the source of infection. Pathogenic fungi in the Netherlands often concern M.canis, T.rubrum, T.mentagrophutes and epidermophyton floccosum.
Is ringworm contagious?
Carriership
Many animals, as well as humans, can be symptomless carriers of the fungal spores that cause ringworm. They then carry the spores of the fungus, but do not notice it. In the meantime, they can transmit the fungus to others. The infection can be transmitted in several ways:
- from animal to human;
- from person to person; or
- from human to animal.
How does contamination occur?
Ringworm is highly contagious and you can become infected in several ways:
- through contact with an infected person;
- through contact with an infected animal;
- by using a contaminated object.
Fungus penetrates the skin
The fungal spores can easily penetrate wet, slightly softened or damaged skin. This can also happen through the environment, for example through a dog basket or cat basket, or through horse blankets, saddles and brushes. Veterinarians and (livestock) farmers are especially susceptible to ringworm; they are easily infected by the animals they work with every day. Young children can also easily become infected through intensive contact and cuddling with a dog or cat. After the fungus has penetrated the skin, it takes about 2 to 3 weeks before the first symptoms are observed.
Ringworm / Source: ProjectManhattan, Wikimedia Commons (CC BY-SA-3.0)
Symptoms of ringworm in humans
Ringworm spots are red and round and get bigger. The rings are sharply defined and the border area is slightly raised and shows redness. The edges start to flake and sometimes small pimples are visible. The spot in the middle will eventually become somewhat lighter in color as healing occurs. A mild degree of itching or burning occurs, but the area usually does not hurt. The spots can appear anywhere on the body, including on the hairy scalp. The spots will disappear spontaneously, although this may take some time. In people with a reduced immune system, fungus can penetrate deeper into the skin, which can lead to serious and painful skin infections.
Examination and diagnosis
Physical examination and fungal culture
The GP can often make the diagnosis by sight, as the abnormalities in ringworm are very characteristic. The doctor can also examine a number of flakes of the affected area under a microscope. A fungal culture can also be made. DNA analysis (using PCR technique) can detect the fungus within a week.
Erythema multiforme / Source: Grook Da Oger, Wikimedia Commons (CC BY-SA-3.0)
Differential diagnosis
Ringworm can be very similar to a number of other conditions, including:
Granuloma annulare;
- Pssoriasis;
- Nummular eczema;
- Atopic eczema;
- Seborrheic eczema;
- Candida;
- Erythrasma;
- Granuloma faciale;
- Subacute cutaneous LE;
- Erythema multiforme;
- Erythema annulare centrifugum;
- Porokeratosis;
Pityriasis rosea on lower leg / Source: Aceofhearts1968, Wikimedia Commons (Public domain)
- Impetigo;
- Parapsoriasis;
- Pityriasis rosea;
- Lymphocytic infiltration of the skin;
- Erythema migrans arciforme et palpabile (EMAP);
- Syphilis.
Treatment of ringworm
Fungi are combated with an antifungal, that is, an antifungal drug. These come in the form of creams, lotions, ointments that you apply locally, and tablets to take. A locally applied antifungal cream is often sufficient to combat ringworm. Anti-fungal creams are available with a prescription, but there are also anti-fungal creams that you can buy without a prescription at the drugstore or pharmacy. If a liniment does not provide sufficient relief, or if it concerns an extensive fungal infection, it may be wise to take antifungal tablets (systemic antifungals). This is only done on doctor’s prescription.
Prognosis
Ringworm can be cured with the right treatment. Ringworm usually disappears after two to three weeks of treatment. Complications are rare and may include a secondary bacterial skin infection or a widespread fungal infection. This last complication is extremely rare and occurs mainly in people with a suppressed or damaged immune system.
Prevention
You can take a number of measures yourself to prevent ringworm or prevent its further spread:
- Avoid skin contact with infected people and animals;
- Wash your hands after petting an animal;
- Keep the skin dry and dry your skin well after showering or bathing (and don’t forget the skin folds);
- Check your pets regularly for flaking spots;
- If you suspect that your pet has ringworm, you can get a fungicide from the vet;
- Do not share clothing and utensils (e.g. hairbrush or hat) with others if you have ringworm.
read more
- Ringworm: symptoms and treatment tinea corporis
- Red ring on skin: erythema annulare centrifugum (EAC)
- Shingles: Symptoms, Causes, Treatment & Contagious
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