Tinea capitis in the Americas: Epidemiological Trends and Etiological Distribution from a Systematic Review

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript presents a systematic review examining the epidemiological trends and etiological distribution of tinea capitis throughout the Americas. In my opinion, the topic is clinically relevant and of considerable public health importance, particularly given the dynamic nature of dermatophyte epidemiology and the continuing burden of tinea capitis among pediatric populations worldwide.

One of the main strengths of the manuscript is its broad geographic scope. By including studies from North America, Central America, the Caribbean, and South America, the authors provide a valuable overview of regional differences in causative dermatophyte species and highlight important epidemiological patterns that may influence diagnostic and therapeutic decision-making.

I also appreciate the effort to synthesize data from multiple countries and to identify the contrasting predominance of Microsporum canis and Trichophyton tonsurans across different regions. These observations have practical implications for clinicians and public health authorities involved in the management and prevention of dermatophytosis.

Overall, the manuscript is well structured and informative. However, several aspects could be strengthened to improve its scientific impact and interpretability.

Major Comments

1. Epidemiological trends versus epidemiological distribution

The title emphasizes epidemiological trends; however, much of the manuscript focuses on geographical distribution rather than temporal evolution. While regional differences are clearly described, I would have liked to see a more detailed analysis of changes over time. For example, the increasing emergence of anthropophilic species such as Trichophyton tonsurans is mentioned repeatedly, but temporal trends are not systematically analyzed. A more explicit discussion of how species distribution has evolved over recent decades would strengthen the manuscript and better align it with its stated objective.

2. Quality assessment of included studies

I was surprised that no formal assessment of study quality or risk of bias was presented. Considering that the review includes observational studies, prevalence studies, case series, and case reports, substantial variability in methodological quality can reasonably be expected. Although the primary objective is descriptive, I believe the inclusion of at least a basic appraisal of study quality would help readers better interpret the reliability of the available evidence.

3. Clinical implications

The discussion appropriately summarizes regional differences in etiological agents. However, from a clinical perspective, the practical implications of these findings could be explored in greater detail. For instance, how should regional differences influence empirical treatment strategies, diagnostic algorithms, or public health interventions? A more clinically oriented discussion would increase the translational value of the review.

4. Diagnostic heterogeneity

The authors acknowledge important variability in diagnostic approaches among included studies. In my opinion, this issue deserves greater emphasis because differences in culture techniques, species identification methods, and laboratory expertise may substantially influence the reported epidemiology. A more detailed discussion of how diagnostic heterogeneity may affect comparisons between countries and regions would strengthen the manuscript.

Minor Comments

1. Several sections of the Discussion largely repeat findings already presented in the Results section. Greater emphasis on interpretation rather than repetition would improve readability.

2. The role of migration and globalization in changing dermatophyte epidemiology is briefly discussed but deserves additional attention, particularly regarding the emergence of traditionally African species in North America.

3. Future perspectives could include a brief discussion of molecular diagnostic techniques and their potential impact on epidemiological surveillance.

Overall Assessment

In my opinion, this review provides a useful and comprehensive overview of the epidemiology of tinea capitis across the Americas. The broad geographic coverage and large number of included studies represent important strengths. Nevertheless, the manuscript would benefit from a more critical appraisal of the available evidence, greater emphasis on temporal epidemiological trends, and a stronger discussion of the clinical implications of the observed regional differences. These revisions would substantially improve the scientific value and practical relevance of the work.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors,

Your manuscript addresses an important and clinically relevant topic by providing a broad overview of the epidemiology and etiological distribution of tinea capitis across the Americas. The geographic scope is extensive, and the compilation of studies from multiple countries may represent a valuable contribution to the literature. However, several important methodological and reporting issues should be addressed before the manuscript can be considered for publication.

Major comments:

1. The review is presented as a systematic review, but several key methodological elements are insufficiently reported. The complete search strategy for each database should be provided, and the study selection process should be described in greater detail. The review was not prospectively registered, which should be acknowledged more explicitly as a limitation.

2. The PRISMA flow diagram contains inconsistencies. The numbers reported in the figure do not fully match those described in the text, and several exclusion categories appear duplicated. The entire flow chart should be carefully revised.

3. The inclusion of case reports and very small case series raises concerns regarding the epidemiological interpretation of the results. Studies reporting single cases contribute little to the assessment of regional epidemiological patterns and may introduce bias. The authors should justify their inclusion or consider restricting the analysis to epidemiological studies with adequate sample sizes.

4. The methodological quality assessment is insufficiently reported. Although the Joanna Briggs Institute tools were used, no detailed results of the risk-of-bias assessment are presented. A summary table or figure showing study quality should be included.

5. The manuscript relies exclusively on narrative synthesis. Given the large number of included studies, additional quantitative summaries would substantially strengthen the paper. At minimum, the authors should provide aggregated regional distributions of the principal dermatophyte species and, if feasible, temporal trends.

6. Table 1 is extremely large and combines studies with vastly different methodological designs and sample sizes. A study reporting a single case is presented alongside studies including hundreds of thousands of patients. Consider moving the full table to supplementary material and providing a more concise summary table in the main text.

7. The discussion mainly restates the results and would benefit from a deeper interpretation of the observed epidemiological patterns. Greater attention should be given to the potential influence of migration, urbanization, socioeconomic conditions, animal exposure, and changing demographic patterns.

8. The reference list requires careful verification. Several references appear unrelated to tinea capitis epidemiology or do not seem to correspond to the information presented in the manuscript. The authors should thoroughly review all citations and ensure that each reference is appropriate and accurately supports the associated statement.

Minor comments:

1. Some taxonomic names should be checked for consistency throughout the manuscript.

2. Consider including a map summarizing the predominant etiological agents by country or region.

3. The conclusions could be shortened and focused more specifically on the principal epidemiological findings.

 

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The paper can be accepted for publication. 

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for considering my comments