Fungal infections cause high rates of morbidity and mortality worldwide, particularly invasive fungal infections, which can be life-threatening in immunocompromised individuals, including patients with neutropenia, hematologic malignancies, and solid organ or hematopoietic stem cell transplants, in whom the likelihood of contracting a fungal infection is increased. However, nontraditional risk factors, such as influenza and COVID-19, have been recognized, putting a high percentage of the population at risk of contracting an invasive fungal infection. Additionally, infectious agents that can cause other mycoses, such as dermatophytosis, chromoblastomycosis, sporotrichosis, cryptococcosis, and histoplasmosis, are of great relevance in the context of ongoing climate change, as this may be associated with an increase in the number of cases of these mycoses.

The emergence of resistant species, such as A. fumigatus, resistant to first-line treatment, is mainly due to environmental mutations caused by the excessive use of fungicides that confer resistance to wild-type strains and infect humans, leading to therapeutic failures. Also affecting the agricultural industry and animals infected by Aspergillus species is the presence of mycotoxins such as aflatoxins, and fungal infections in the veterinary field. Similarly, C. parapsilosis is resistant to fluconazole and responsible for large outbreaks worldwide. The rise of emerging fungal agents such as C. auris and A. terreus warrants updating the epidemiology, as well as understanding the susceptibility profiles in each region and hospital. Thus, the scientific and integrated analysis of the impact of fungal infections contributes to a unified approach to human, animal, and ecosystem health.

Infections such as those caused by Candida spp. and Aspergillus spp., distributed worldwide, have shown that the existence of diagnostic tools is still insufficient. Rapid, sensitive, specific, easy-to-perform, and inexpensive tests are required to ensure widespread availability, even in developing countries. At the same time, the approach and management of these patients also remain a challenge. Although new therapeutic options are under development and research, such as Olorofim, Fosmanogepix, Ibrexafungerp, and Rezafungin, there is still a need to expand the knowledge base regarding these biologics for their application.

Therefore, it is imperative to recognize alternative and novel therapeutic options, diagnostic tools, and epidemiological findings that allow for a prompt and effective approach to fungal infections. In this special issue, we aim to bring together advances in our understanding of epidemiology, susceptibility patterns, diagnostic tools, and therapeutic options. This collection includes opinion pieces, commentaries, systematic reviews, and original research articles. Topics include, among others, studies on:
• Recognition of new risk factors in invasive and noninvasive fungal infections;
• New epidemiological overview of fungal agents of medical, animal and agricultural importance worldwide;
• Development of rapid diagnostic tests, screening, and surveillance for fungal infections;
• Recent advances in the development of new drugs;
• Advances in our understanding of susceptibility patterns of invasive and noninvasive fungal agents.

Impact

Frontiers in Tropical Diseases

Antimicrobial Resistance