LONG-TERM SURVIVAL OF PSEUDOGYMNOASCUS DESTRUCTANS AT ELEVATED TEMPERATURES

Area of Science:

• Mycology
• Veterinary Science
• Ecology

Background:

• White-nose syndrome (WNS) is a devastating fungal disease impacting hibernating bat populations in North America.
• The causative agent, *Pseudogymnoascus destructans* (PD), is a psychrophilic fungus.
• Limited experimental data exists on PD's survival on active bats or in environments outside hibernacula.

Purpose of the Study:

• To experimentally determine the survival duration of *Pseudogymnoascus destructans* conidia at temperatures relevant to active bats and the external environment.
• To assess PD survival on artificial growth media and natural bat fur.
• To evaluate the potential for PD to be dispersed by active bats.

Main Methods:

• An in vitro culture-based approach was employed to study PD conidia survival.
• Conidia were incubated on artificial media (including brain-heart infusion agar with sheep blood) and bat fur.
• Incubation temperatures simulated conditions on active bats or in the external environment: 24°C, 30°C, and 37°C.

Main Results:

• PD conidia survived for up to 150 days on artificial media at 24°C, 60 days at 30°C, and 15 days at 37°C.
• On bat fur, viable PD was recovered for 180 days at 24°C, 60 days at 30°C, and 5 days at 37°C.
• Maximal survival on artificial media was observed on brain-heart infusion agar with sheep blood.

Conclusions:

• Viable *Pseudogymnoascus destructans* conidia can persist on bat fur for extended periods at temperatures encountered by active bats.
• These findings support the hypothesis that bats can act as vectors for long-distance PD dispersal.
• Further research is needed to assess PD viability on various fomites for each specific substrate.