Outbreak of Tinea capitis caused by Microsporum ferrugineum in Thailand

Area of Science:

• Mycology
• Dermatology
• Infectious Diseases

Background:

• An outbreak of Tinea capitis, a fungal infection of the scalp, occurred in 1993 at a facility for infants in Bangkok, Thailand.
• The study investigated the clinical presentation, causative agents, and treatment efficacy for this outbreak.

Purpose of the Study:

• To identify the primary pathogen responsible for the Tinea capitis outbreak.
• To evaluate the effectiveness of griseofulvin and selenium sulfide shampoos in treating the infection.
• To assess the clinical characteristics and diagnostic accuracy of laboratory methods.

Main Methods:

• Clinical diagnosis and laboratory investigations including Wood's light examination, KOH preparation, and fungal culture were performed on 138 cases.
• Microscopic and cultural identification of fungal species.
• Treatment involved griseofulvin (10-15 mg/kg/day) and selenium sulfide shampoos.

Main Results:

• Microsporum ferrugineum was identified as the predominant pathogen (66.7%), frequently causing a non-inflammatory form of Tinea capitis.
• Diagnostic methods showed varying positivity rates: Wood's light (89.9%), KOH preparation (75.9%), and fungal culture (27.4%).
• The combination therapy resulted in an 84.8% cure rate within an average of 14.9 weeks, with no reported recurrences or adverse effects.

Conclusions:

• Microsporum ferrugineum was the main cause of the Tinea capitis outbreak.
• Griseofulvin combined with selenium sulfide shampoos is an effective treatment for Tinea capitis in infants.
• Early diagnosis and appropriate treatment are crucial for managing fungal scalp infections in vulnerable populations.