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Bat white-nose syndrome in North America

* The newly described fungus, Geomyces destructans, causes an invasive skin infection in bats and is the likely agent of white-nose syndrome (WNS). * With immune system functions and body temperatures reduced during hibernation, bats may be unusually susceptible to a pathogenic fungus such as G. destructans. * WNS was first observed in a popular show cave near Albany, New York, leading some investigators to suspect that a visitor inadvertently introduced G. destructans at this site, triggering a wider WNS outbreak in North America. * Biologists trying to manage WNS within North American bat populations face major challenges, including the variety of susceptible host species, incredible dispersal capabilities of bats, difficulties in treating such populations, and persistence of the pathogen in their vulnerable underground habitats.

Microbe Magazine

Evidence for occurrence, persistence, and growth potential of Escherichia coli and enterococci in Hawaii’s soil environments

High densities of Escherichia coli and enterococci are common in freshwaters on Oahu and other Hawaiian Islands. Soil along stream banks has long been suspected as the likely source of these bacteria; however, the extent of their occurrence and distribution in a wide range of soils remained unknown until the current investigation. Soil samples representing the seven major soil associations were collected on the island of Oahu and analyzed for fecal coliforms, E. coli , and enterococci by the most probable number method. Fecal coliforms, E. coli , and enterococci were found in most of the samples analyzed; log mean densities (MPN ± SE g soil −1 ) were 1.96±0.18, n =61; 1.21±0.17, n =57; and 2.99±0.12, n =62, respectively. Representative, presumptive cultures of E. coli and enterococci collected from the various soils were identified and further speciated using the API scheme; at least six species of Enterococcus , including Enterococcus faecalis and Enterococcus faecium , were identified. In mesocosm studies, E. coli and enterococci increased by 100-fold in 4 days, after mixing sewage-spiked soil (one part) with autoclaved soil (nine parts). E. coli remained metabolically active in the soil and readily responded to nutrients, as evidenced by increased dehydrogenase activity. Collectively, these findings indicate that populations of E. coli and enterococci are part of the natural soil microflora, potentially influencing the quality of nearby water bodies.

Hawai'i

Bats prove to be rich reservoirs for emerging viruses

Emerging pathogens, many of them viruses, continue to surprise us, providing many newly recognized diseases to study and to try to control. Many of these emergent viruses are zoonotic, transmitted from reservoirs in wild or domestic animals to humans, either by insect vectors or by exposure to the droppings or tissues of such animals. One rich- but, until recently, underappreciated-source of emergent viruses is bats ( Chiroptera , meaning "hand wing"). Accounting for 1,116, or nearly one fourth, of the 4,600 recognized species of mammals, bats are grouped into two suborders Megachiroptera, which contains a single family, Pteropodidae, consisting of 42 genera and 186 species, and Microchiroptera, which contains 17 families, 160 genera, and 930 species. Although bats are among the most abundant, diverse, and geographically dispersed orders of terrestrial mammals, research on these flying mammals historically focused more on their habits and outward characteristics than on their role in carrying microorganisms and transmitting pathogens to other species. Even in those cases where bats were known to carry particular pathogens, the microbiologists who studied those pathogens typically knew little about the bat hosts. Hence, investigators now are seeking to explain how variations of anatomy, physiology, ecology, and behavior influence the roles of bats as hosts for viral pathogens.

Microbe