Northern Kentucky University
Decontamination Strategies to Stop the Spread of White-Nose Syndrome
Institution
Northern Kentucky University
Faculty Advisor/ Mentor
Hazel Barton
Abstract
Since 2006, White-Nose Syndrome (WNS) caused by the fungus Geomyces destructans has been decimating hibernating bat populations in caves in the Northeastern US, including the endangered Indiana (Myotis sodalist) and Gray (Myotis grisescens) bat populations. The epidemiology of G. destructans suggests that the fungus may be transmitted from cave to cave by the ropes and equipment used by cavers, or from bat to bat by bat researchers. We therefore focused on finding a protocol for disinfecting caving equipment by testing the efficacy of readily available household cleaning agents and organic compounds in killing fungal spores using three different assays: 1) a disk diffusion assay; 2) a germination assay; and 3) a growth assay. To avoid using the pathogenic G. destructans, we substituted the closely related species Geomyces pannorum. Our work suggested that washing equipment with a surfactant, such as Woolite, was critical to removing clays and muds that inhibit the functioning of disinfectants, followed by disinfection with 10% bleach or a 0.1% quaternary ammonium compound (Formula 409) for 10 minutes. We subsequently tested our protocol on climbing ropes and other safety equipment, subjecting these materials to strength tests to determine the risk of structural damage from the protocol. To identify compounds that would target Geomyces species without harming the normal fungal populations that grow in the caves, we tested these compounds against the unrelated Penicillum pinophilium and Aspergillus brasiliensis; those cleaning reagents that killed the Geomyces spores but had no significant effect on other species were tested further. Our results demonstrated effective and easily performed protocols for decontaminating G. destructans from the equipment of cavers and bat researchers, and they do not require a background in microbiology. Our recommendations have been incorporated into the US Fish and Wildlife Service WNS decontamination protocols.
Decontamination Strategies to Stop the Spread of White-Nose Syndrome
Since 2006, White-Nose Syndrome (WNS) caused by the fungus Geomyces destructans has been decimating hibernating bat populations in caves in the Northeastern US, including the endangered Indiana (Myotis sodalist) and Gray (Myotis grisescens) bat populations. The epidemiology of G. destructans suggests that the fungus may be transmitted from cave to cave by the ropes and equipment used by cavers, or from bat to bat by bat researchers. We therefore focused on finding a protocol for disinfecting caving equipment by testing the efficacy of readily available household cleaning agents and organic compounds in killing fungal spores using three different assays: 1) a disk diffusion assay; 2) a germination assay; and 3) a growth assay. To avoid using the pathogenic G. destructans, we substituted the closely related species Geomyces pannorum. Our work suggested that washing equipment with a surfactant, such as Woolite, was critical to removing clays and muds that inhibit the functioning of disinfectants, followed by disinfection with 10% bleach or a 0.1% quaternary ammonium compound (Formula 409) for 10 minutes. We subsequently tested our protocol on climbing ropes and other safety equipment, subjecting these materials to strength tests to determine the risk of structural damage from the protocol. To identify compounds that would target Geomyces species without harming the normal fungal populations that grow in the caves, we tested these compounds against the unrelated Penicillum pinophilium and Aspergillus brasiliensis; those cleaning reagents that killed the Geomyces spores but had no significant effect on other species were tested further. Our results demonstrated effective and easily performed protocols for decontaminating G. destructans from the equipment of cavers and bat researchers, and they do not require a background in microbiology. Our recommendations have been incorporated into the US Fish and Wildlife Service WNS decontamination protocols.