Showing papers by "DeeAnn M. Reeder published in 2014"

Nonlethal screening of bat-wing skin with the use of ultraviolet fluorescence to detect lesions indicative of white-nose syndrome

Abstract: Definitive diagnosis of the bat disease white-nose syndrome (WNS) requires histologic analysis to identify the cutaneous erosions caused by the fungal pathogen Pseudogymnoascus [formerly Geomyces] destructans (Pd). Gross visual inspection does not distinguish bats with or without WNS, and no nonlethal, on-site, preliminary screening methods are available for WNS in bats. We demonstrate that long-wave ultraviolet (UV) light (wavelength 366–385 nm) elicits a distinct orange–yellow fluorescence in bat-wing membranes (skin) that corresponds directly with the fungal cupping erosions in histologic sections of skin that are the current gold standard for diagnosis of WNS. Between March 2009 and April 2012, wing membranes from 168 North American bat carcasses submitted to the US Geological Survey National Wildlife Health Center were examined with the use of both UV light and histology. Comparison of these techniques showed that 98.8% of the bats with foci of orange–yellow wing fluorescence (n = 80) were W...

Host, pathogen, and environmental characteristics predict white-nose syndrome mortality in captive little brown myotis (Myotis lucifugus).

Abstract: An estimated 5.7 million or more bats died in North America between 2006 and 2012 due to infection with the fungus Pseudogymnoascus destructans (Pd) that causes white-nose syndrome (WNS) during hibernation. The behavioral and physiological changes associated with hibernation leave bats vulnerable to WNS, but the persistence of bats within the contaminated regions of North America suggests that survival might vary predictably among individuals or in relation to environmental conditions. To investigate variables influencing WNS mortality, we conducted a captive study of 147 little brown myotis (Myotis lucifugus) inoculated with 0, 500, 5 000, 50 000, or 500 000 Pd conidia and hibernated for five months at either 4 or 10°C. We found that female bats were significantly more likely to survive hibernation, as were bats hibernated at 4°C, and bats with greater body condition at the start of hibernation. Although all bats inoculated with Pd exhibited shorter torpor bouts compared to controls, a characteristic of WNS, only bats inoculated with 500 conidia had significantly lower survival odds compared to controls. These data show that host and environmental characteristics are significant predictors of WNS mortality, and that exposure to up to 500 conidia is sufficient to cause a fatal infection. These results also illustrate a need to quantify dynamics of Pd exposure in free-ranging bats, as dynamics of WNS produced in captive studies inoculating bats with several hundred thousand conidia may differ from those in the wild.

Novel Paramyxovirus Associated with Severe Acute Febrile Disease, South Sudan and Uganda, 2012

Abstract: In 2012, a female wildlife biologist experienced fever, malaise, headache, generalized myalgia and arthralgia, neck stiffness, and a sore throat shortly after returning to the United States from a 6-week field expedition to South Sudan and Uganda. She was hospitalized, after which a maculopapular rash developed and became confluent. When the patient was discharged from the hospital on day 14, arthralgia and myalgia had improved, oropharynx ulcerations had healed, the rash had resolved without desquamation, and blood counts and hepatic enzyme levels were returning to reference levels. After several known suspect pathogens were ruled out as the cause of her illness, deep sequencing and metagenomics analysis revealed a novel paramyxovirus related to rubula-like viruses isolated from fruit bats.

Anti-fungal immune responses to Pseudogymnoasces destructans in bats affected by white-nose syndrome (VET2P.1041)

Abstract: White-nose syndrome is a devastating disease affecting bats in North America. It is caused by Pseudogymnoasces destructans, a fungal pathogen that colonizes the muzzles and wings of hibernating bats. Our study focuses on the relative differences between the immune responses of various bat species to this pathogen. The strength and type of immune response triggered by an antigen can be measured by determining the gene expression profile of cytokines. We have developed a quantitative PCR panel for bat cytokine genes in order to measure the immune responses involved in susceptibility to white-nose syndrome. We also used a cytokine ELISA to determine serum cytokine levels. In addition, we analyzed the neutrophil:lymphocyte ratios from blood smears collected both during hibernation and post hibernation, as another measure of immune response over time. By comparing the relative expression of certain cytokine genes, we can determine which subsets of T cells are mediating the immune response to the fungal pathogen. Our research will shed light on the mechanisms by which some bat species have a higher survival rate, and this knowledge can be used to further develop strategies for protecting North America’s bat population.