Ringworm: Understanding the Causes of a Fungal Skin Infection
Ringworm is a specific type of skin infection caused by dermatophyte fungi. These microorganisms thrive only on hairless skin, an essential characteristic for their development. They feed on the keratin present in the epidermis, which explains its frequent location on the arms, trunk, or face. This infectious agent is mainly transmitted through direct contact with:domestic or farm animals (cats, dogs, horses, etc.) that are asymptomatic carriers of the fungus;
other people who are already infected, particularly via contaminated surfaces or objects in public places; the soil, although this mode of transmission is less common. Professionals who frequently work with animals, such as veterinarians or farmers, as well as children, are particularly at risk. The dermatophyte groups responsible for ringworm
- Dermatophytes are classified into three groups: Zoophiles:
- originating from animals, responsible for infections that are often inflammatory. Anthropophiles:
- transmitted from human to human, frequently encountered in communal settings.Geophiles:
present in the soil, contamination is less common.
This diversity explains the multiplicity of sources of
herpes infection
- and underscores the importance of prevention adapted to the environment. Signs of ringworm: recognizing the characteristic skin lesions
- The diagnosis of ringworm
- is based primarily on careful clinical observation of the lesions. The main distinguishing sign is annular erythema
: one or more well-defined red patches, often circular or oval in shape, with: an active, inflamed, and raised border, sometimes covered with small scales or vesicles;
A rather clear or scarred center, showing healing in progress;
Centrifugal growth, meaning the plaque gradually expands outward. This combination gives the lesions a ring-like or “St. Catherine’s wheel” appearance. They are generally located on the trunk, arms, legs, and sometimes the face. Associated symptoms include:
- often intense itching,
- which can lead to scratching and promote secondary infections;
the appearance of multiple lesions, especially if the source of infection is animal;
a possible severe inflammatory form, called kerion, with raised, oozing lesions.
- Differentiating ringworm from other conditions
- This fungal herpes infection should not be confused with:
- herpes simplex virus,
which manifests as painful, clustered, non-ring-like vesicles; Eczema or psoriasis,
- which have more diffuse, bilateral lesions without a clear border;
- other fungal infections located differently, such as athlete’s foot or tinea capitis.
If in doubt, the doctor can confirm the diagnosis of tinea corporis using an ultraviolet lamp (Wood’s lamp) or a mycological sample.
Treatment of tinea corporis: appropriate care for rapid healing
Treatment of tinea corporis is based primarily on antifungals: antifungal creams or gels
- applied topically twice a day for 2 to 4 weeks in cases of limited lesions; oral medications
- (griseofulvin, terbinafine, itraconazole) if the lesions are multiple, extensive, or resistant;
- sometimes a short course of topical corticosteroids to relieve intense itching. It is essential to continue treatment even after the lesions appear to have disappeared in order to avoid recurrence.
Other hygiene recommendations:do not scratch to prevent bacterial superinfections;
- Eliminate potential sources of contamination, such as infected pets;
- Regularly clean and disinfect clothing, bedding, and surfaces that come into contact with the skin.
These good practices accelerate healing and limit the spread of infection to those around you.
Precautions to prevent the spread:
As a preventative measure, you should:
- Avoid direct contact with other people’s lesions;
- Limit contact with animals that are suspected of having the illness or are sick;
- Monitor pets for symptoms and consult a veterinarian if necessary;
- Maintain rigorous personal hygiene, especially in communal settings.
