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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

Main Article

Table 2

Iridovirusesa,b of herpetofauna (34)

Host Virus Country or region where isolated Ref.
Amphibian iridoviruses Frog virus 3 North America, United States 60
Leopard frog (Rana pipiens) considered type for
sympatric isolates frog
virus 1, 2, 9-23
Red-spotted new eft T6-20 North America, United States 61

(Notophthalamus viridescens)
Bullfrog Tadpole edema virus North America, United States 62

(Rana catesbeiana)
Edible frog (Rana esculenta) Rana esculenta iridovirus Europe (Croatia) 63
Ornate burrowing frog Bohle iridovirus Australia 64

(Limnodynastes ornatus)
Cane toad (Bufo marinus) Gutapo iridovirus South America (Venezuela) 65
Common frog Rana UK virus Europe, United Kingdom 33

(Rana temporaria)
Common toad (Bufo bufo) Bufo UK virus Europe, United Kingdom 34
Red-legged frog larvae Redwood Creek virus California, United States 66,67

(Rana aurora)
Tiger salamander (Ambystoma A. tigrinum virus Arizona, United States 27

tigrinum stebbinsi)
Tiger salamander (A. t. Regina ranavirus Saskatchewan, Canada 36

mavortium)
Ranid frog (Rana grylio) Rana grylio virus China 68
Tiger salamander Not yet named N. Dakota, United States 35

(A. tigrinum)
Spotted salamander Not yet named Maine, United States 35

(A. maculatum)
Tiger salamander Not yet named Utah, United States 35

(A. tigrinum)
Reptile iridoviruses
Box turtle (Terrapene c. Turtle virus 3 Maryland, United States 69

carolina)
Central Asian tortoise Tortoise virus 5 North America, United States 69

(Testudo horsfieldi)
Soft-shelled turtle China 70

(Trionyx sinensis)
Green tree python Wamen virus Australia A.D.

(Chondropython viridis) Hyatt (unpubl. obs.)
Gopher tortoise North America, United States 69

(Gopherus polyphemus)

aErythrocytic viruses, which are antigenically unrelated to ranaviruses and are not associated with amphibian mass deaths or declines, are not included. Further work is required to evaluate their significance.
bThere is little variation in the major capsid protein (a major antigen of this group of viruses) within the genus Ranavirus (<4% difference at the nucleotide and amino acid level; Hyatt, unpubl. obs). This high degree of homology is interesting, as some of these viruses do not appear to be species specific. No discriminating neutralizing antibodies exist, and ranaviruses are identified and characterized by a range of techniques, including antigen capture enzyme-linked immunosorbent assay, polyacrylamide gel electrophoresis, restriction endonuclease digestion, polymerase chain reaction, and sequencing and in situ hybridization (67,71).
cWhere no name has been given, the virus has not yet been named. 

Main Article

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

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