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Global Zoonotic Diseases: Fungal Diseases

Global Zoonotic Diseases: Fungal Diseases

Disease in Humans

Causative Organism

Animals Involved

Geographic Distribution

Probable Means of Transmission to Humans

Clinical Manifestations in Humans

Blastomyces dermatitidis, B helicus, B percursus, B gilchristii, possibly others

Many mammals including dogs, cats, horses, marine mammals; B helicus might be associated with burrows of small mammals

Distribution in environment uncertain; clinical cases focal; locally acquired cases reported in parts of North America, Africa, Middle East, India; some Blastomyces species can occur in areas where B dermatitidis is not usual

Environmental exposure, eg, moist soil (infection common to humans and animals; also reported rarely by animal exposure (eg, bite from infected pet kinkajou)

Acute to chronic pulmonary disease; skin or bone lesions; meningitis, other syndromes, disseminated disease possible; course mild to severe, some cases fatal

Coccidioides immitis, C posadasii

Cattle, sheep, horses, llamas, dogs, many other mammals

Especially southwestern US, Mexico, Central and South America; in arid or semiarid foci; some cases might be acquired outside usual foci

Principally environmental exposure (inhalation of arthrospores), including fungal cultures (infection common to humans and animals), one unusual case reported after postmortem examination of horse with disseminated disease

Self-limited, febrile, flu-like illness, sometimes with cough, chest pain in healthy host; serious, possibly life-threatening pulmonary disease or disseminated infection with cutaneous/subcutaneous lesions, persistent meningitis or osteomyelitis, especially in immunocompromised

Cryptococcus neoformansvar grubii, C neoformans var neoformans, C gattii

(Organism from environment grows well in bird or bat guano; temporary colonization of avian intestinal tract also possible); clinical cases in various mammals


Principally environmental exposure, via inhalation or through the skin (infection common to humans and animals), caution warranted around accumulations of bird or bat feces; rare cases associated with pet birds

Respiratory signs, mild to severe, often self-limiting in healthy host but more likely to be severe in immunocompromised; dissemination with CNS disease, ocular signs, other syndromes, most often in immunocompromised; skin lesions, either localized from inoculation (uncommon) or from disseminated disease

Histoplasma capsulatum var capsulatum

Organism from environment grows well in bird or bat guano; infections in many domestic and wild mammals including bats and birds

Worldwide; clinical cases often cluster in regional foci

Principally environmental exposure (infection common to humans and animals), caution warranted around concentrations of bat guano (eg, caves)

Flu-like, febrile illness, usually self-limiting in healthy hosts; skin lesions; chronic pulmonary disease, usually with preexisting lung disease; dissemination in very young, elderly, immunocompromised

H capsulatum var duboisii

Organism from environment grows well in bird or bat guano; infections in many domestic and wild mammals including bats and birds


Principally environmental exposure (infection common to humans and animals), caution warranted around concentrations of bat guano (eg, caves)

Usually skin and subcutaneous lesions, osteolytic bone lesions but can disseminate or cause lesions (eg, brain abscess) in other tissues

Malassezia infection

Malassezia spp adapted to animals (eg, M pachydermatis)

Dogs, cats, other animals


Exposure to clinically affected animals; normal levels on skin not thought to be an important risk

Dermatitis; zoonotic organisms might be implicated in fungemia, invasive disease in preterm neonates, other immunocompromised

Microsporum and Trichophyton spp

Dogs, cats, hedgehogs, cattle, sheep, goats, horses, rodents, other mammals, birds, very rarely reptiles


Direct skin or hair contact with infected animals, fomites

Skin and hair lesions, usually pruritic; rare skin dissemination in immunocompromised

Sporothrix schenckii complex members, especially S schenckii sensu stricto, S brasiliensis and S globosa

Cats, other mammals, birds, possibly reptiles; cats are more likely to transmit organism to humans than other species

Worldwide; species of Sporothrix may differ in distribution; epizootics in cats in South America

Primarily environmental in vegetation, wood, soil; inoculation from environment in penetrating wounds (eg, splinters, bites, pecks) is most common source, skin contact with lesions, especially in cats also possible; bites, scratches, other close contact implicated during feline epizootics; inhalation rare

Papules, pustules, nodules, ulcerative skin lesions, may follow course of draining lymphatics; mucosa can be affected; extracutaneous involvement, especially bones, joints; disseminated disease (including meningitis) can occur in immunocompromised; acute or chronic pulmonary disease resembling tuberculosis after inhalation, especially with underlying lung disease (rare)


Talaromyces (Penicillium) marneffei; uncertain zoonotic potential

Organism very common in asymptomatic cotton rats in the genera Rhizomys and Cannomys and their burrows; also found in dogs and other mammals


Probably acquired from the soil (infection common to humans and animals); most infected humans have no known exposure to bamboo rats; zoonotic potential unclear

Commonly a febrile illness with generalized lymphadenopathy, non-productive cough; often mild in healthy humans; disseminated disease mainly in immunosuppressed, can involve many organs including lung, liver, spleen, lymph nodes, skin, intestinal tract and infrequently CNS; numerous umbilicated or ulcerated skin lesions a common syndrome, often affect the face and neck