Prevalence of tinea capitis among schoolchildren in Mahajanga, northern Madagascar: An epidemio-clinical survey using conventional, proteomic and molecular approaches

Objectives: This study aimed to determine the prevalence, clinical, and epidemiological features of tinea capitis (TC) in schoolchildren in Mahajanga city, north-west Madagascar, to identify the etiological dermatophyte species by morphological, proteomic and molecular approaches and ultimately to analyze the risk factors promoting TC in the studied region.

Methods: A survey was conducted in a randomly selected primary school. Symptomatic schoolchildren with signs resembling TC were sampled by scraping and sterile swabbing after examination of the scalp with a Wood's lamp. The collected specimens were then analyzed by a combination of conventional, proteomic, and molecular examinations RESULTS: The results of this study revealed a prevalence of TC of 8.7 % (39/449). Boys were much more affected than girls (M/F = 3.3). A little more than half (53.8 %) of TC cases exhibited large (>2 cm) alopecic patches. Pruritus was the most frequent clinical sign in 74.4 % of cases. The incriminated species identified by morphology and confirmed by MALDI-TOF mass spectrometry and ITS sequencing were exclusively Microsporum audouinii. Playing football, running and contact with animals were statistically associated with TC. Inversely, the use of soap and the application of styling oil were protective against TC.

Conclusion: In this first investigation carried out in Mahajanga city, the prevalence of TC was 8.7 % and M. audouinii was the only responsible agent identified by three methods. Molecular approach allowed identification of the dermatophyte species in the specimens with inconclusive culture but positive direct examination. The risk factors such as playing football, running and contact with animals were significantly associated with TC.