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Wallemia sebi

Mitosporic fungus. Hyphomycetes.
Distribution Where Found Mode of Dissemination
Ubiquitous;
cosmopolitan.
Monotypic.
Soil, good stuffs, hay, textiles. Grows on salted fish. Dry spore.
Wind.
Allergen Potential Opportunist or Pathogen Potential Toxin Production
Known allergen.
Type I allergies (hay fever, asthma).
Rare human abscess reported. Walleminol, tryptophol and UCA 1064-beta.
Growth Indoors Industrial Uses Other Comments
Wallemia grows on relatively dry surfaces; found on wood in crawl spaces. Common in mattress dust; may colonize human skin scales.
Aw=0.69-0.75
Not known. Wallemia is a keratinophilic, osmophilic fungus (grows on highly concentrated solutions e.g. salt and sugar).
Characteristics: Growth/Culture Notes on Spore Trap Recognition Notes on Tape Lift Recognition
Poor growth on general fungal media. Grows on specialized fungal media with high osmotic pressure. Forms very small tan elevated colonies on DG18 and MEA. While an occasional colony will appear on malt agar, Wallemia may be missed when this is the only media used. Very small cubical (initially) light brown spores formed in chains of four. Recognizable when young, fresh, and when still in chains. Distinctive and identifiable on tape lifts. Observation of sporulating structures may require 1000X magnification (oil immersion).
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