White-Nose Syndrome Fungus: A Generalist Pathogen of Hibernating Bats

Abstract

Host traits and phylogeny can determine infection risk by driving pathogen transmission and its ability to infect new hosts. Predicting such risks is critical when designing disease mitigation strategies, and especially as regards wildlife, where intensive management is often advocated or prevented by economic and/or practical reasons. We investigated Pseudogymnoascus [Geomyces] destructans infection, the cause of white-nose syndrome (WNS), in relation to chiropteran ecology, behaviour and phylogenetics. While this fungus has caused devastating declines in North American bat populations, there have been no apparent population changes attributable to the disease in Europe. We screened 276 bats of 15 species from hibernacula in the Czech Republic over 2012 and 2013, and provided histopathological evidence for 11 European species positive for WNS. With the exception of Myotis myotis, the other ten species are all new reports for WNS in Europe. Of these, M. emarginatus, Eptesicus nilssonii, Rhinolophus hipposideros, Barbastella barbastellus and Plecotus auritus are new to the list of P. destructans-infected bat species. While the infected species are all statistically phylogenetically related, WNS affects bats from two suborders. These are ecologically diverse and adopt a wide range of hibernating strategies. Occurrence of WNS in distantly related bat species with diverse ecology suggests that the pathogen may be a generalist and that all bats hibernating within the distribution range of P. destructans may be at risk of infection.

Destructin-1 is a collagen-degrading endopeptidase secreted by Pseudogymnoascus destructans , the causative agent of white-nose syndrome

“…Infection involves deep penetration of the subcutaneous tissue by fungal hyphae, causing ulcerative necrosis and tissue destruction (7,(9)(10)(11). P. destructans typically forms more superficial infections in European bat populations, with no evidence for associated mortality (9,12), although a recent study also found evidence of invasive WNS lesions in European bats (13). Current models suggest that P. destructans is an invasive species that originated in Europe, where native bat species may be more resistant to the most debilitating forms of the disease (9).…”

First confirmation of Pseudogymnoascus destructans in British bats and hibernacula

“…It has now been confirmed in at least 14 European countries and is suspected in four more due to convincing photographic evidence (Frick and others, 2014) from 18 bat species (Martínková and others 2010, Wibbelt and others 2010, Puechmaille and others 2011, Zukal and others 2014). However, there has been no known incidence of mass mortality of bats due to P. destructans in Continental Europe (Puechmaille and others 2011).…”

White-Nose Syndrome in Bats

“…mystacinus, M. blythii, M. daubentonii, M. brandtii, M. emarginatus, M. nattereri, M. bechsteinii and M. escalerai/sp. A. The list of species with P. destructans infection is likely to increase as sampling intensity increases as illustrated by the recent Zukal et al (2014) study which reported infection of a few individuals from three more species of the family Vespertilionidae, Eptesicus nilssonii, Plecotus auritus and Barbastella Barbastellus, as well as on a single individual of Rhinolophus hipposideros, of the family Rhinolophidae.…”

“…In Europe, P. destructans invasion of the wing membrane is generally restricted to the epidermis and adnexae without deep invasion into the underlying connective tissue but with occasional formation of neutrophilic pustules, contrasting with the common and extensive invasion of dermal connective tissue in bats from North America (Pikula et al 2012;Wibbelt et al 2013;Zukal et al 2014;Bandouchova et al 2015). Based on investigation of two euthanized individuals, P. destructans invasion in the skin of the muzzle seems to be more pronounced than invasion of the wing membrane (Pikula et al 2012;Wibbelt et al 2013).…”

“…This has led to confusion and some debate about whether the term WNS should be used to describe infections occurring in Europe, which are pathologically similar to those in North America but which do not include mass mortality or aberrant winter behaviour (Puechmaille et al 2011a). Despite its original definition as a syndrome (Veilleux 2008;Reeder and Turner 2008;Turner and Reeder 2009), the term WNS is now routinely used to refer the cutaneous infection caused by P. destructans, which have been documented in Europe (Pikula et al 2012;Wibbelt et al 2013;Zukal et al 2014). Some have advocated a name change to clarify a difference between a 'syndrome' and a 'disease' caused by fungal infection (Chaturvedi and Chaturvedi 2011).…”