Michael O’Connor | Geology Reports

USGS2017

Bat white-nose syndrome: a real-time TaqMan polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructans tructans.

The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg of genomic DNA from G. destructans . The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was further qualified by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific, and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.

Mycologia↗

USGS2013

Distribution and environmental persistence of the causative agent of white-nose syndrome, Geomyces destructans , in bat hibernacula of the eastern United States

White-nose syndrome (WNS) is an emerging disease of hibernating bats caused by the recently described fungus Geomyces destructans . First isolated in 2008, the origins of this fungus in North America and its ability to persist in the environment remain undefined. To investigate the correlation between manifestation of WNS and distribution of G. destructans in the U.S., we analyzed sediment samples collected from 55 bat hibernacula (caves and mines) both within and outside the known range of WNS using a newly developed real-time PCR assay. Geomyces destructans was detected in 17 of 21 sites within the known range of WNS at the time the samples were collected; the fungus was not found in 28 sites beyond the known range of the disease at the time that environmental samples were collected. These data indicate that distribution of G. destructans is correlated with disease in hibernating bats and support the hypothesis that the fungus is likely an exotic species in North America. Additionally, we examined whether G. destructans persists in infested bat hibernacula when bats are absent. Sediment samples were collected from 14 WNS-positive hibernacula, and the samples were screened for viable fungus using a culture technique. Viable G. destructans was cultivated from 7 of the 14 sites sampled during late summer when bats were no longer in hibernation, suggesting the fungus can persist in the environment in the absence of bat hosts for long periods of time.

Applied and Environmental Microbiology↗