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Volume 5, Number 6—December 1999
Perspective

Emerging Infectious Diseases and Amphibian Population Declines

Peter Daszak*Comments to Author , Lee Berger†‡, Andrew A. Cunningham§, Alex D. Hyatt†, D. Earl Green¶, and Rick Speare‡
Author affiliations: *Institute of Ecology, University of Georgia, Athens, Georgia, USA; †Australian Animal Health Laboratory, Commonwealth Scientific Industrial Research Organization, Geelong, Victoria, Australia; ‡School of Public Health and Tropical Medicine, James Cook University, Townsville, Queensland, Australia; §Institute of Zoology, Zoological Society of London, London, United Kingdom; and ¶National Wildlife Health Center, U.S. Geological Survey, Madison, Wisconsin, USA

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Figure 2

Scanning electron micrograph of digital skin of a wild frog (Litoria lesueuri, from Queensland, Australia) that died of cutaneous chytridiomycosis. Many cells within this area of the superficial layer of the epidermis contain mature sporangia, and unopened discharge tubes are visible protruding through infected cells. The skin was fixed in 2.5% glutaraldehyde, postfixed in 1% osmium tetroxide, dehydrated, critical-point-dried, sputter coated with gold, and examined with a JEOL JSM 840 scanning e

Figure 2. Scanning electron micrograph of digital skin of a wild frog (Litoria lesueuri, from Queensland, Australia) that died of cutaneous chytridiomycosis. Many cells within this area of the superficial layer of the epidermis contain mature sporangia, and unopened discharge tubes are visible protruding through infected cells. The skin was fixed in 2.5% glutaraldehyde, postfixed in 1% osmium tetroxide, dehydrated, critical-point-dried, sputter coated with gold, and examined with a JEOL JSM 840 scanning electron microscope at 5 kV. All specimens are from animals that were naturally infected and died due to chytridiomycosis in montane rain forest regions of Panama and Australia. Bar = 5 µm. Photo courtesy of L. Berger, reprinted with permission from A. Campbell (29).

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1Note that the relative number of mass death events decreases with increasing impact on population.

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