Ringworm (Tinea) Global Prevalence: ~10% of Population Affected Annually

Ringworm (dermatophytosis) is a **superficial fungal infection** of skin, hair, or nails caused by dermatophytes (Trichophyton, Microsporum, Epidermophyton).

Epidemiology

• Global prevalence: ~10–15% of population at any time; ~797 million cases annually (based on 8B population × 10%).
• High‑burden regions: Tropical/subtropical, crowded living, limited hygiene access.
• Age: Children (tinea capitis), adolescents/young adults (tinea corporis, cruris, pedis).
• Risk factors: Humidity, occlusive footwear, sports (wrestling), immunosuppression, animal contact.

Clinical Forms

• Tinea corporis: Annular, scaly, erythematous plaques with central clearing.
• Tinea pedis (athlete’s foot): Interdigital maceration, scaling, vesicles.
• Tinea cruris (jock itch): Groin folds.
• Tinea capitis: Scalp scaling, alopecia, kerion (inflammatory).
• Tinea unguium (onychomycosis): Thickened, discolored nails.

Treatment

• Topical azoles (clotrimazole, terbinafine) × 2–4 wks (skin).
• Oral terbinafine, itraconazole, griseofulvin (scalp, nails, extensive).
• Hygiene: dry thoroughly, avoid sharing towels/clothing, treat pets.

Highly treatable; recurrence common if predisposing factors persist.