U.S. Geological Survey "Fish Disease Leaflet 83" Author Denies Applicability of Refractory Studies in U.S.!
For months now we have talked on the Koi Club of the Air with those in the effected fish breeding and dealing industry in states around the Great Lakes about this devastating disease and the impacts of APHIS regulations designed to prevent the spread. Many in the koi-hobby have claimed based on USGS "Fish Disease Leaflet 83" that koi like carp noted in the study are refractory (immune) to the disease.After careful consideration of the variable nature of genotype data and the potential that the applicable studies had not been done on the latest variance of the disease, which appeared in the U.S. a Freedom of Information request was made to the U.S.G.S. In the response the author of the "Fish Disease Leaflet 83" acknowledges that the refractory data was related to genotypes found in Europe and the Middle East that according toU.S.G.S. data are not applicable to the strain present in the U.S.
The following is an excerpt from "Fish Disease Leaflet 83," which has led some be believe koi are resistant to this disease, "Host Susceptibility: Fish shown by experimental challenge to be susceptible to VHS virus infection are Atlantic salmon, Salmo salar; brook trout, Salvelinus fontinalis; golden trout, O. aguabonita; rainbow trout x coho salmon hybrids; giebel, Carassius auratus gibelio; sea bass, Dicentrarchus labrax; and turbot, Scophthalmus maximus (de Kinkelin and Castric 1982; Castric and de Kinkelin 1984; Wolf 1988). Fish shown by experimental challenges to be refractory to VHS virus infection are common carp, Cyprinus carpio; chub, Leuciscus cephalus; Eurasian perch, Perca fluviatilis; roach, L. rutilus; and tench, Tinca tinca. http://www.lsc.usgs.gov/fhb/leaflets/83.asp"
Now consider the genotype distribution of the disease prior to reading McAllister's complete FOI response.
What are the genotypes involved? “Four genotypes of VHS virus have been identified, and appear to be distributed geographically, rather than by host or year of epizootic occurrence. Genotypes I, II, and III are mainly found in Europe and Japan , while isolates of genotype IV have been recovered only from fish in North America , Japan and Korea . The pathogenicity of VHS virus varies by genotype and species affected. The VHSV isolates originating from wild marine fish show no or low pathogenicity in rainbow trout and Atlantic salmon, although several are pathogenic to turbot. The European/Asian freshwater isolates are highly pathogenic to rainbow trout.”
Furthermore, "The number of different species that are known to be susceptible to the Great Lakes strain of VHS virus is increasing and detailed information on the status of other Great Lakes species of fish regarding their susceptibility to VHS is not known. http://www.aphis.usda.gov/vs/ceah/cei/taf/emergingdiseasenotice_files/vhsgreatlakes.htm"
United States Department of Interior
U.S. Geological Survey
Deborah Kimball, USGS FOIA Officer
January 18, 2007
Dear Mr. Hawley:
This is in response to your Freedom of Information Act (FOIA) request dated January 2, 2007, and received in this office on January 2, 2007. In your request you sought supporting scientific documentation for the assertion made in “Fish Disease Leaflet 83” that demonstrates that “fish shown by experimental challengers to be refractory to VHS virus infection are common carp, Cyprinus carpio, chub, Leuciscus cephalus, Eurasian perch, Perca fluviatilis, roach, L. rutilus, and tech, Tinca tinca.”
In response to your request, I contacted Mr. Philip E. McAllister and he has provided the following response:
Regarding the FOI request for supporting scientific documentation for an assertion made in “Fish Disease Leaflet 83,” the information requested is not available and thus cannot be provided for the following reasons:
1). Fish Disease Leaflet 83 (FDL-83) is a review publication that summarized scientific information and does not contain original research conducted by the author. Thus, the author does not have supporting documentation other than reprints of peer reviewed journal articles.
2). The peer reviewed journals used for the review are listed in the “Literature Cited” section of FDL-83. The journal articles with their scientific findings are most probably available on the internet by Google Scholar search. The term “viral hemorrhagic septicemia virus” should be keyed into the search engine.
3) The studies of interest were performed in Europe and the Middle East. At that time in history (1980’s-early 1990’s), live fish studies involving viral hemorrhagic septicemia virus (VHSV) were prohibited in the United States.
4). At that time in history (1980’s-early 1990’s), the process of genotyping fish viruses was in its infancy. Thus, the scientific documentation to “determine, which type of VHS genotype was studied and if refractory studies have been conducted on genotype IV,” does not exist. The studies conducted by European and Middle East laboratories utilized immersion exposure challenges to European serotypes of VHSV. The North American type of VHSV from the Pacific Northwest had been recently discovered and not yet been genetically characterized.