Fungal pathogens

Based on:
Ecker DJ, Sampath R, Willett P, Wyatt JR, Samant V, Massire C, Hall TA, Hari K, McNeil JA, Büchen-Osmond C, Budowle B. The Microbial Rosetta Stone Database: A compilation of global and emerging infectious microorganisms and bioterrorist threat agents BMC Microbiol. 2005; 5: 19.

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Ascomycota

cellular organisms – Eukaryota – Fungi/Metazoa group – Fungi – Dikarya – Ascomycota –

Transmission	Importance	Disease description	Selected literature
Leotiomyceta – Sordariomyceta – Sordariomycetes – Hypocreomycetidae – Hypocreales – mitosporic Hypocreales – Fusarium – Fusarium oxysporum species complex – Fusarium oxysporum
In most cases, causes plant infections. Routes of transmission are not described. Infections are rare and occur mostly in immunocompromized patients.	Emergent Infectious Agent; Medically Important Human Pathogen	The spectrum of cutaneous involvement related to Fusarium spp. includes toxic reactions, colonization, superficial indolent infection, deep cutaneous or subcutaneous infections and disseminated infection.	Boutati EI et al. (Blood. 1997); “Fusarium oxysporum”[title]
Taphrinomycotina – Pneumocystidomycetes – Pneumocystidales – Pneumocystidaceae – Pneumocystis – Pneumocystis jirovecii
Nosocomial (hospital-acquired), airborne infections.	Emergent Infectious Agent; Medically Important Human Pathogen	Causes pneumonia in immunocompromized patients.	Nevez G et al. (Parasite. 2008); “Pneumocystis jirovecii”[title]
Leotiomyceta – Eurotiomycetes – Eurotiomycetidae – Eurotiales – Trichocomaceae – mitosporic Trichocomaceae – Aspergillus – Aspergillus flavus
Airborne; enters body through inhalation or wound contamination.	Medically Important Human Pathogen	Chronic granulomatous sinusitis, keratitis, cutaneous aspergillosis, wound infections and osteomyelitis following trauma and inoculation.	Hedayati MT et al. (Microbiology. 2007); Krishnan S et al. (Mycoses. 2009); “Aspergillus flavus”[title]
Leotiomyceta – Eurotiomycetes – Eurotiomycetidae – Eurotiales – Trichocomaceae – mitosporic Trichocomaceae – Aspergillus – Aspergillus fumigatus
The most ubiquitous of the airborne saprophytic fungi. Humans and animals inhale conidia and fragments of mycelium of this fungus. Environmental exposure is main route of the infection.	Medically Important Human Pathogen	Causes invasive aspergillosis (IA) in the immunocompromised patient population. IA is a devastating illness, with mortality rates in some patient groups reaching as high as 90%.	Latgé JP. (Clin Microbiol Rev. 1999); Dagenais TR et al. (Clin Microbiol Rev. 2009); “Aspergillus fumigatus”[title]
Leotiomyceta – Eurotiomycetes – Eurotiomycetidae – Eurotiales – Trichocomaceae – mitosporic Trichocomaceae – Aspergillus – Aspergillus niger
Ubiquitous airborne saprophytic fungi. Humans and animals inhale conidia and fragments of mycelium of this fungus. Environmental exposure is main route of the infection.	Medically Important Human Pathogen	Citric acid and many A. niger enzymes are considered GRAS by FDA, however, the fungus is an opportunistic pathogen and can cause mycoses in immunocompromized patients (cutaneous and ear canal infections, tracheobronchitis have been reported). Invasive aspegilloses are rare.	Baker SE. (Med Mycol. 2006); “Aspergillus niger”[title]
Leotiomyceta – Eurotiomycetes – Eurotiomycetidae – Onygenales – mitosporic Onygenales – Coccidioides – Coccidioides immitis Coccidioides posadasii
Soil-dwelling fungi endemic in the United States, Mexico, and Central and South America. Contracted by inhalation of airborne arthroconidia.	Emergent Infectious Agent; Medically Important Human Pathogen; CDC Notifiable Agent; Potential Biological Weapon; HHS Select Pathogen; USDA High Consequence Animal Pathogen	In humans causes coccidiomycosis (Valley Fever) manifested in pneumonia. Cases of extrapulmonary infections such as endocarditis and meningitis have been reported in immunocompromized patients.	Coccidioides posadasii/immitis: taxonomy, facts, life cycle, tissues, mating types at MetaPathogen
Saccharomyceta – Saccharomycotina – Saccharomycetes – Saccharomycetales – mitosporic Saccharomycetales – Candida – Candida albicans
Ubiquitous fungus, often commensal microorganism in humans that can initiate an opportunistic infection in immunocompromized patients. Nosocomial transmissions (hospital-acquired) are not uncommon.	Emergent Infectious Agent; Medically Important Human Pathogen	Causes candidiases that include oropharyngeal and alimentary tract candidiasis, denture stomatitis, endocarditis, catheter-related candidemia and candiduria.	Dongari-Bagtzoglou A et al. (PLoS One. 2009); “Candida albicans”[title]

Basidiomycota

cellular organisms – Eukaryota – Fungi/Metazoa group – Fungi – Dikarya – Basidiomycota –

Transmission	Importance	Disease description	Selected literature
Agaricomycotina – Tremellomycetes – Tremellales – Tremellaceae – Filobasidiella – Filobasidiella/Cryptococcus neoformans species complex – Filobasidiella neoformans
Distributed worldwide and is often found in soil contaminated by avian feces. Inhalation of airborne propagules from an environmental source is main pathway of infection.	Emergent Infectious Agent; Medically Important Human Pathogen; Potential Biological Weapon	Causes cryptococcosis, also known as Busse-Buschke disease, a disease that ranges from asymptomatic infection of airways to severe meningitis.	Cryptococcus neoformans/Filobasidiella neoformans, causative agent of cryptococcosis: life cycle, tissues and mating types at MetaPathogen
Agaricomycotina – Tremellomycetes – Tremellales – mitosporic Tremellales – Trichosporon
Widely distributed in nature and can occasionally belong to the human microbiota; may enter the body by ingestion, inhalation or wound contamination.	Medically Important Human Pathogen	Ca cause fungemia, endocarditis, invasive cutaneous and intestinal mycoses in immunocompromized individuals.	Chagas-Neto TC et al. (Mycopathologia. 2008); “Trichosporon”[title]

Microsporidia

cellular organisms – Eukaryota – Fungi/Metazoa group – Fungi – Dikarya – Microsporidia –

Transmission	Importance	Disease description	Selected literature
Apansporoblastina – Unikaryonidae – Encephalitozoon – Encephalitozoon cuniculi
Transmissions occur via the oral route either by ingestion of contaminated tissues and other foods or by ingestion of infected urine, perhaps on food, or when animals lick the coats of others. Transplacental transmission may occur.	Emergent Infectious Agent; Zoonotic Agent; Medically Important Human Pathogen; NIAID Category B Priority Pathogen	A widespread and often sub-clinical microsporidian parasite of homeothermic animals, including humans. Persistent or self-limiting diarrhea are the most common symptoms associated with microsporidiosis in immune-deficient or immune-competent individuals.	Wasson K, Peper RL. (Vet Pathol. 2000); Wilson JM. (Med Biol. 1979); “Encephalitozoon cuniculi”
Apansporoblastina – Enterocytozoonidae – Enterocytozoon – Enterocytozoon bieneusi
Identified in environmental sources, especially in surface water, as well as in wild, domestic and farm animals; waterborne, foodborne and zoonotic transmissions are possible route of infections.	Emergent Infectious Agent; Zoonotic Agent; Medically Important Human Pathogen; NIAID Category B Priority Pathogen	The most common microsporidian species identified in humans. Has been identified in a broad range of human populations that, in addition to persons with HIV infection, includes travelers, children, organ transplant recipients, and the elderly. Persistent or self-limiting diarrhea are the most common symptoms.	Feng X et al. (Antimicrob Agents Chemother. 2009); Thellier M et al. (Parasite. 2008); “Enterocytozoon bieneusi”

Mucoromycotina

cellular organisms – Eukaryota – Fungi/Metazoa group – Fungi – Fungi incertae sedis – Basal fungal lineages – Mucoromycotina – Mucorales –

Transmission	Importance	Disease description	Selected literature
Mucoraceae – Mucor – Mucor circinelloides Mucoraceae – Rhizopus – Rhizopus oryzae Lichtheimiaceae – Lichtheimia – Lichtheimia corymbifera
Nosocomial transmissions (hospital-acquired) are most common. Sources of infection have included elastoplast adhesive bandage rolls, ventilation systems, wooden tongue depressors, karaya (plant-derived adhesive) ostomy bags, and water damage to a linen store and patient shower room.	Medically Important Human Pathogen	Cause two forms of mycosis: mucormycosis, an acute, necrotic, rapidly progressive disease of the immunocompromised patient that may lead to death; and entomophthoromycosis is a chronic, slowly progressive subcutaneous disease seen mostly in immunocompetent patients living in tropical climates.	Kamei K. (Mycopathologia. 2001); Ribes JA et al. (Clin Microbiol Rev. 2000); Spellberg B et al. (Clin Infect Dis. 2009); Elgart ML. (Dermatol Clin. 1996); “Mucormycosis”[Majr]