Skip to content
naulon

No retraction, correction or concern found when last checked on Oct 18, 2026.

The Still Underestimated Problem of Fungal Diseases Worldwide

Fausto Almeida, Marcio L. Rodrigues, Carolina Coelho

Frontiers in Microbiology · 2019 · Review

doi:10.3389/fmicb.2019.00214

Abstract

In the past few years, fungal diseases caused estimated over 1.6 million deaths annually and over one billion people suffer from severe fungal diseases (Brown et al., 2012; Anonymous, 2017b). Public health surveillance of fungal diseases is generally not compulsory, suggesting that most estimates are conservative (Casadevall, 2017; Anonymous, 2017a). Fungal disease can also damage plants and crops, causing major losses in agricultural activities and food production (Savary et al., 2012). Animal pathogenic fungi are threatening bats, amphibians and reptiles with extinction (Casadevall, 2017). It is estimated that fungi are the highest threat for animal-host and plant-host species, representing the major cause (approximately 65%) of pathogen-driven host loss (Fisher et al., 2012). In this complex scenario, it is now clear that the global warming and accompanying climate changes have resulted in increased incidence of many fungal diseases (Garcia-Solache and Casadevall, 2010). On the basis of all these factors, concerns on the occurrence of a pandemic of fungal origin in a near future have been raised (Casadevall, 2017). In this context, to stop forgetting and underestimating fungal diseases is mandatory.

Full text

From PubMed Central, U.S. National Library of Medicine, as current on Oct 18, 2026. Paragraph numbers are ours, so an answer can point at one.

The Burden of Human Fungal Infections

Currently, there are few antifungal drugs approved for use in humans. The last antifungals approved for human use were characterized in 2002. This scenario may be linked to an imbalance between funding and mortality rates in the field of fungal diseases. For instance, cryptococcal meningitis results in approximately 180 000 deaths annually globally, as compared to 429 000 deaths caused by malaria or 1.6 million tuberculosis-deaths (as estimated by WHO in 2015 and 2017, respectively). However, cryptococcosis received less than 0.5% of the global research and development funding, while malaria and tuberculosis received together 35.5% of the total investment in research and development in infectious diseases. Current therapeutic to treat fungal diseases remain unsatisfactory, and to develop novel therapeutic alternatives a significant investment in dedicated research is required. Novel antifungal are in different clinical development stages, and these new compounds such as AR-12, BHBM, CD101, E1210/11, F901318, Ilicicolin H, Nikkomycin Z, Sampangine, Scy-078, Sertraline, T-2307, Tamoxifen, and VT-1129. Some of these (VT-119 and Nikkomycin Z, for example) belong to new classes of drugs, i.e., they act through different mechanisms and molecular targets than the already approved drugs, and may provide a much-needed extension to the limited therapies currently available. Programs specifically offering funding to mycological research are necessary to potentiate further development of effective antifungal therapy and ultimately reduce mortality from fungal diseases.

The Impact of Fungal Infections on Food Crops and Disproportionate Impact in Developing Countries

Fungal diseases in developing countries demand special attention. Many of the fungal diseases in Latin America are often overlooked, although they clearly fulfill the criteria to be classified as neglected human diseases. The general impact of fungal pathogens on human health goes beyond the ability of fungi to infect humans, since they destroy a third of all food crops annually, causing economical loss and impacting global poverty. Statistics from the 2009–2010 world harvest (www.fao.org or FAOSTAT1) suggest fungi-induced losses in five of the most important crops globally (rice, wheat, maize, potatoes, and soybean). If those losses were mitigated, these crops would have been enough to feed 8.5% of the seven billion populations in 2011. Furthermore, in a hypothetical event where these five crops were affected simultaneously, approximately 61% of the world’s population would not have food. The most economically devastating fungi are Magnaporthe oryzae, affecting rice and wheat, followed by Botrytis cinerea, which has a broad host range and Puccinia spp., affecting wheat. Several high-value crops produced in the tropics, such as bananas, coffee, cacao, spices, mangos, and several nuts, are currently affected by fungal infections and these crops are not produced colder climates. Therefore dependence of crop produced in tropical regions aggravated with a lack of biodefense and preparedness might result in disastrous economical consequences worldwide.

Fungal infections of invertebrate hosts may also impact agricultural crises due to ecological imbalance. For instance, bee broods are susceptible to fungal infections caused by genera of Ascosphaera and Aspergillus, and the agricultural production worldwide is highly dependent on pollination mediated by bees. Fungal infection of bees may precipitate a disaster, with unpreceded impact on agriculture and various plant species.

The Impact of Fungal Infections on Animal Species

When fungi cause animal disease the outcomes are quite dramatic and scientists have been trying to raise attention to the effects of fungal infections in decreasing biodiversity, an effect aggravated (if not triggered) by global warming. Bat decimation caused by Geomyces destructans and several frog species by Batrachochytrium dendrobatidis are well known events. In invertebrates we already mentioned the case of bees, and further species may be affected but further research is needed. For example, there is a debate regarding if a marine Aspergillus spp. is associated with the decline of coral reefs. Overall, the examples of species decimation in mammals, plants, and bees by fungal pathogens should prompt investigation of similar phenomenon in a wider scale, for example, other insects and in aquatic life.

Critical Interactions of Fungi With the Environment

It is important to highlight that most of the plant-fungal interactions are beneficial to both plants and fungi, with this symbiotic interaction improving plant growth, development, foraging, acquisition of soil resources, and tolerance to stress. For instance, Trichoderma induces biofertilization of crops. The addition of Trichoderma hamatum or Trichoderma koningii to the production fields can increase crop productivity up to 300%. Trichoderma spp. also acts in the mycoparasitism, the direct attack of one fungal species on another, being described as potential biological control agent against important phytopathogenic fungi such as Fusarium spp., Rhizoctonia solani, Sclerotium rolfsii, Sclerotinia sclerotiorum, B. cinerea, and Pythium spp.. Thus, mycoparasitism-based strategies could decrease the use of agrochemicals and antifungals in crop cultivation. In this sense, a better understanding of the fungal diversity and its impact on plant-fungal interactions would be highly beneficial to improve phytopathogen control.

The Urgency of Combatting Fungal Infections

The reduced number of antifungals impact human health not only due to lack of therapy to cure human patients. Medically approved antifungal drugs have been used for agricultural purposes for decades. Most human pathogens have environmental niches, implying that the agricultural use of medically-approved drugs imposes the concrete risk of fostering drug resistance. Emergence of antifungal resistance can endanger the already limited treatments options, with calamitous effects for treatment outcomes. The development of new antifungal drugs is urgent to improve both human health and agricultural production.

The worsening of global warming opens a Pandora box for fungal diseases. Some thermally intolerant fungi with current pathogenic potential should acquire the ability to survive at mammalian temperatures. This threat is heightened since some fungi can take advantage of a natural selection-adaptation strategy, and consequently to adapt to higher temperature by thermal selection.

The collaboration between all these affected disciplines would be critical in facilitating at detecting epidemics early on and preventing further spread. The concept of One Health, with integration and communication between medical doctors, veterinarians, and food safety officials has been implemented with remarkable success and should become a standard for transmissible diseases. We have included a table summarizing basic information regarding distribution and etiological agent of important human mycoses (Table 1).

The negative impact of any infectious disease is usually higher in neglected populations. Lack of access to healthcare, underfunded healthcare, and delayed diagnosis lead to higher burden of fungal diseases. The economy of countries in developing countries strongly relies on agricultural production. Another fungal blight, if not managed properly, can still have disastrous economical and societal consequences.

The old adage “know your enemy” illustrates the major point of this essay: significant investment in fungal research, including fungal biology, human and plant pathogenicity, therapeutic agents, diagnostic tools, and vaccines, has the potential to avoid a global catastrophe. This call has been made by most, if not all, prominent fungal researchers. We urge more attention to fungal biology and pathogenesis globally with special attention to diseases affecting developing countries, as a safeguard for prevention of losses in agriculture, environmental losses, and damage to human health.

Author Contributions

All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

References 72

  1. 1.

    Agarwal A. K. Xu T. Jacob M. R. Feng Q. Lorenz M. C. Walker L. A. (2008 ). Role of heme in the antifungal activity of the azaoxoaporphine alkaloid sampangine. Eukaryot. Cell 7 387–400.

    Not in our library10.1128/ec.00323-07

  2. 2.

    Aizen M. A. Garibaldi L. A. Cunningham S. A. Klein A. M. (2009 ). How much does agriculture depend on pollinators? Lessons from long-term trends in crop production. Ann. Bot. 103 1579–1588.

    Not in our library10.1093/aob/mcp076

  3. 3.

    Almeida F. Wolf J. M. Casadevall A. (2015 ). Virulence-associated enzymes of Cryptococcus neoformans. Eukaryot. Cell 14 1173–1185.

    Not in our library10.1128/ec.00103-15

  4. 4.

    Almeida F. B. Cerqueira F. M. Silva Rdo N. Ulhoa C. J. Lima A. L. (2007 ). Mycoparasitism studies of Trichoderma harzianum strains against Rhizoctonia solani: evaluation of coiling and hydrolytic enzyme production. Biotechnol. Lett. 29 1189–1193.

    Not in our library10.1007/s10529-007-9372-z

  5. 5.

    Anonymous (2017a ). Stop neglecting fungi. Nat. Microbiol. 2:17120.

    Not in our library10.1038/nmicrobiol.2017.120

  6. 6.

    Anonymous (2017b ). The Burden of Fungal Disease, on LIFE. Available at: http://go.nature.com/2sMKpuN

    Not in our library

  7. 7.

    Azevedo M. M. Faria-Ramos I. Cruz L. C. Pina-Vaz C. Rodrigues A. G. (2015 ). Genesis of azole antifungal resistance from agriculture to clinical settings. J. Agric. Food Chem. 63 7463–7468.

    Not in our library10.1021/acs.jafc.5b02728

  8. 8.

    Baxter B. K. DiDone L. Ogu D. Schor S. Krysan D. J. (2011 ). Identification, in vitro activity and mode of action of phosphoinositide-dependent-1 kinase inhibitors as antifungal molecules. ACS Chem. Biol. 6 502–510.

    Not in our library10.1021/cb100399x

  9. 9.

    Benitez T. Rincon A. M. Limon M. C. Codon A. C. (2004 ). Biocontrol mechanisms of Trichoderma strains. Int. Microbiol. 7 249–260.

    Not in our library

  10. 10.

    Bitencourt T. A. Rezende C. P. Quaresemin N. R. Moreno P. Hatanaka O. Rossi A. (2018 ). Extracellular vesicles from the dermatophyte trichophyton interdigitale modulate macrophage and keratinocyte Functions. Front. Immunol. 9:2343.

    Not in our library10.3389/fimmu.2018.02343

  11. 11.
  12. 12.

    Brown G. D. Denning D. W. Gow N. A. R. Levitz S. M. Netea M. G. White T. C. (2012 ). Hidden killers: human fungal infections. Sci. Transl. Med. 4:165rv13.

    Not in our library10.1126/scitranslmed.3004404

  13. 13.

    Cano M. V. Hajjeh R. A. (2001 ). The epidemiology of histoplasmosis: a review. Semin. Respir. Infect. 16 109–118.

    Not in our library10.1053/srin.2001.24241

  14. 14.

    Casadevall A. (2017 ). Don’t forget the fungi when considering global catastrophic biorisks. Health Secur. 15 341–342.

    Not in our library10.1089/hs.2017.0048

  15. 15.
  16. 16.

    Casadevall A. Perfect J. R. (1998 ). Cryptococcus Neoformans. Washington, DC: ASM Press

    Not in our library10.1128/9781555818241

  17. 17.

    Castillo C. G. Kauffman C. A. Miceli M. H. (2016 ). Blastomycosis. Infect. Dis. Clin. North Am. 30 247–264.

    Not in our library10.1016/j.idc.2015.10.002

  18. 18.

    Chakrabarti A. Bonifaz A. Gutierrez-Galhardo M. C. Mochizuki T. Li S. (2015 ). Global epidemiology of sporotrichosis. Med. Mycol. 53 3–14.

    Not in our library10.1093/mmy/myu062

  19. 19.

    Coelho C. Casadevall A. (2016 ). Cryptococcal therapies and drug targets: the old, the new and the promising. Cell Microbiol. 18 792–799.

    Not in our library10.1111/cmi.12590

  20. 20.

    Colombo A. L. Tobon A. Restrepo A. Queiroz-Telles F. Nucci M. (2011 ). Epidemiology of endemic systemic fungal infections in Latin America. Med. Mycol. 49 785–798.

    Not in our library10.3109/13693786.2011.577821

  21. 21.

    Conceicao-Silva F. Morgado F. N. (2018 ). Immunopathogenesis of human sporotrichosis: what we already know. J. Fungi 4:E89.

    Not in our library10.3390/jof4030089

  22. 22.

    de Crecy E. Jaronski S. Lyons B. Lyons T. J. Keyhani N. O. (2009 ). Directed evolution of a filamentous fungus for thermotolerance. BMC Biotechnol. 9:74.

    Not in our library10.1186/1472-6750-9-74

  23. 23.

    Dean R. Van Kan J. A. Pretorius Z. A. Hammond-Kosack K. E. Di Pietro A. Spanu P. D. (2012 ). The Top 10 fungal pathogens in molecular plant pathology. Mol. Plant Pathol. 13 414–430.

    Not in our library10.1111/j.1364-3703.2011.00783.x

  24. 24.

    Dolan K. Montgomery S. Buchheit B. Didone L. Wellington M. Krysan D. J. (2009 ). Antifungal activity of tamoxifen: in vitro and in vivo activities and mechanistic characterization. Antimicrob. Agents Chemother. 53 3337–3346.

    Not in our library10.1128/aac.01564-08

  25. 25.

    Douglas C. M. Foor F. Marrinan J. A. Morin N. Nielsen J. B. Dahl A. M. (1994 ). The saccharomyces-cerevisiae Fks1 (Etg1) gene encodes an integral membrane-protein which is a subunit of 1,3-beta-D-glucan synthase. Proc. Natl. Acad. Sci. U.S.A. 91 12907–12911.

    Not in our library10.1073/pnas.91.26.12907

  26. 26.

    Drenth A. Guest D. I. (2016 ). Fungal and oomycete diseases of tropical tree fruit crops. Annu. Rev. Phytopathol. 54 373–395.

    Not in our library10.1146/annurev-phyto-080615-095944

  27. 27.

    Fisher M. C. Henk D. A. Briggs C. J. Brownstein J. S. Madoff L. C. McCraw S. L. (2012 ). Emerging fungal threats to animal, plant and ecosystem health. Nature 484 186–194.

    Not in our library10.1038/nature10947

  28. 28.

    Garcia-Solache M. A. Casadevall A. (2010 ). Global warming will bring new fungal diseases for mammals. MBio 1:e00061-10.

    Not in our library10.1128/mbio.00061-10

  29. 29.

    Ghosh P. N. Fisher M. C. Bates K. A. (2018 ). Diagnosing emerging fungal threats: a one health perspective. Front. Genet. 9:376.

    Not in our library10.3389/fgene.2018.00376

  30. 30.

    Guimaraes A. J. Nosanchuk J. D. Zancope-Oliveira R. M. (2006 ). Diagnosis of histoplasmosis. Braz. J. Microbiol. 37 1–13.

    Not in our library10.1590/s1517-83822006000100001

  31. 31.

    Harman G. E. Howell C. R. Viterbo A. Chet I. Lorito M. (2004 ). Trichoderma species - opportunistic, avirulent plant symbionts. Nat. Rev. Microbiol. 2 43–56.

    Not in our library10.1038/nrmicro797

  32. 32.

    Hector R. F. Zimmer B. L. Pappagianis D. (1990 ). Evaluation of nikkomycins X and Z in murine models of coccidioidomycosis, histoplasmosis, and blastomycosis. Antimicrob. Agents Chemother. 34 587–593.

    Not in our library10.1128/aac.34.4.587

  33. 33.

    Heitman J. Kozel T. R. Kwon-Chung J. Perfect J. R. Casadevall A. (2011 ). Cryptococcus: From Human Pathogen to Model Yeast. Washington, DC: ASM Press.

    Not in our library

  34. 34.

    Jensen A. B. Aronstein K. Flores J. M. Vojvodic S. Palacio M. A. Spivak M. (2013 ). Standardmethods for fungal brood disease research. J. Apic. Res. 52 1–39.

    Not in our library10.3896/ibra.1.52.1.13

  35. 35.

    Kim K. Harvell C. D. (2004 ). The rise and fall of a six-year coral-fungal epizootic. Am. Nat. 164(Suppl. 5), S52–S63.

    Not in our library10.1086/424609

  36. 36.

    King L. J. Anderson L. R. Blackmore C. G. Blackwell M. J. Lautner E. A. Marcus L. C. (2008 ). Executive summary of the AVMA One health initiative task force report. J. Am. Vet. Med. Assoc. 233 259–261.

    Not in our library10.2460/javma.233.2.259

  37. 37.

    Latge J. P. (1999 ). Aspergillus fumigatus and aspergillosis. Clin. Microbiol. Rev. 12 310–350.

    Not in our library10.1128/cmr.12.2.310

  38. 38.

    Lepak A. J. Marchillo K. Andes D. R. (2015 ). Pharmacodynamic target evaluation of a novel oral glucan synthase inhibitor, SCY-078 (MK-3118), using an in vivo murine invasive candidiasis model. Antimicrob. Agents Chemother. 59 1265–1272.

    Not in our library10.1128/aac.04445-14

  39. 39.

    McBride J. A. Gauthier G. M. Klein B. S. (2017 ). Clinical manifestations and treatment of blastomycosis. Clin. Chest. Med. 38 435–449.

    Not in our library10.1016/j.ccm.2017.04.006

  40. 40.

    Mitsuyama J. Nomura N. Hashimoto K. Yamada E. Nishikawa H. Kaeriyama M. (2008 ). In vitro and in vivo antifungal activities of T-2307, a novel arylamidine. Antimicrob. Agents Chemother. 52 1318–1324.

    Not in our library10.1128/aac.01159-07

All 72 references

Cited by papers we hold 5

Reads

Read by people on this page

None yet.

Checked or read by AI through naulon

None yet.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.

Are you an author?

Is this your paper?

Claim it to add your note and be paid when agents cite it. Free.