APHIS AND WHO PLAN TO EXEMPT THE ATYPICAL SCRAPIE NOR-98 FROM REGULATIONS AT MEETING THIS MONTH
USDA's Deputy Secretary Talks with Sheep Producers
May 1, 2009 - "Life in rural America is intimately integrated with production agriculture," said Kathleen Merrigan, deputy secretary for the U.S. Department of Agriculture (USDA), when she addressed the more than 50 sheep producers from around the country who were in Washington, D.C., this week. "I am very interested in looking for new ways for farmers to market their products and for them to grab a little more of the food dollar. The connection between the food that consumers eat and the farms that the food is grown on must be closer, and I look forward to working with producers to affect that."
snip...
According to Jere Dick, DVM, associate deputy administrator and chief of field operations for the Animal and Plant Health Inspection Service (APHIS), "We anticipate discussions and hopefully revisions of the scrapie chapter at the World Organization for Animal Health meeting this month. The revisions will likely exclude Nor-98 like scrapie from classical scrapie regulations. If this is done, APHIS will be able to exempt flocks with Nor-98 like scrapie cases, should they occur, from extensive flock depopulation actions."
snip...end
http://sheepusa.org/?page=site/newsande ... cf744f349a
snip...
Nor98-like Scrapie in the United States of America
was presented by Drs. Christina M. Loiacono, S. Mark Hall, and Bruce V. Thomsen, National Veterinary Services Laboratory, USDA-APHIS-VS.
This paper describes the first six sheep diagnosed with Nor98-like disease in the United States and serves to acknowledge the increased efforts of diagnosticians and the USDA program to control and eradicate scrapie disease. Classical scrapie, a fatal neurodegenerative disease affecting the central nervous system of sheep and goats, is among a number of diseases classified as transmissible spongiform encephalopathies (TSEs). Recently, a distinct strain of scrapie was diagnosed in sheep in Norway1 and has been identified in numerous countries of the European Union (EU). The disease has been identified, among other names, as Nor98 or Nor98-like scrapie. Distinctions between classical scrapie and Nor98-like scrapie are made based on signalment, clinical signs, histopathology and immunodiagnostic results. In the past, the classical scrapie disease was confirmed by examination of the brain tissue for a triad of histopathological signs - vacuolation, loss of neurons and gliosis - and, more recently, by immunohistochemical (IHC) or biochemical detection of abnormal prion protein (PrPSc) in the brain, or lymphoid tissues. In the case of Nor98-like scrapie there is generally little or no vacuolation in the brain and, to date, no lymphoid accumulation of PrPSc has been detected. Classical scrapie typically has the most intense PrPSc immunostaining at the obex (motor nucleus of the vagus), while this area is spared in Nor98-like scrapie. Alternatively, Nor98-like scrapie consistently has PrPSc immunostaining in the spinal nucleus of the trigeminal nerve and variable, but often an intense immunostaining for PrPSc in the cerebellum. Thus the diagnosis of Nor98 and Nor98-like disease can be based on immunohistochemistry identifying abnormal prion protein in regions of the brain not typically associated with classical scrapie. Additionally there is a distinct diagnostic western blot pattern for Nor98 and Nor-98 like disease consisting of three or more protein bands with the unglycosylated band being less than 15 kd, compared to classical scrapie in which the unglycosylated band is greater than 15 kd. Nor98 and Nor-98 like disease is associated with older sheep, usually greater than four years of age, while sheep in the range of three to five years of age are more commonly affected by classical scrapie. Clinical signs are uncommon with Nor98 and Nor98-like disease but when present most often include ataxia without pruritis. Genotypes known to provide sheep with resistance to classical scrapie are not spared from Nor98 and Nor98-like disease.
The six U.S. cases had no clinical signs reported. Three cases were detected during slaughter surveillance, two were detected as a result of classical scrapie being found in the flock, one found during testing associated with diagnostic necropsy. Five of the 6 cases had genotypes that are susceptible to classical scrapie and one was AARR. Only one Nor98-like scrapie case was found per flock.
1. Benestad SL, Sarradin P, Thu B, Schönheit J, Tranulis MA, Bratberg B., Cases of scrapie with unusual features in Norway and designation of a new type, Nor98. Vet. Rec.
http://www.usaha.org/committees/reports ... r-2008.pdf
http://www.sheepusa.org/index.phtml?pag ... adff9d89bc
http://www.sheepusa.org/index.phtml?pag ... 42526bd9ee
http://www.animalagriculture.org/Procee ... herine.pdf
NOW, if there have been more of the Nor-98 documented to date, know one would know since NO MAP for the Nor-98 total cases in the USA is posted on the USDA/APHIS scrapie maps monthly report. ...TSS
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form of scrapie was first described in Norway in 1998. Several features of Nor98 were shown to be different from classical scrapie including the distribution of disease associated prion protein (PrPd) accumulation in the brain. The cerebellum is generally the most affected brain area in Nor98. The study here presented aimed at adding information on the neuropathology in the cerebellum of Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A panel of histochemical and immunohistochemical (IHC) stainings such as IHC for PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers for phagocytic cells were conducted. The type of histological lesions and tissue reactions were evaluated. The types of PrPd deposition were characterized. The cerebellar cortex was regularly affected, even though there was a variation in the severity of the lesions from case to case. Neuropil vacuolation was more marked in the molecular layer, but affected also the granular cell layer. There was a loss of granule cells. Punctate deposition of PrPd was characteristic. It was morphologically and in distribution identical with that of synaptophysin, suggesting that PrPd accumulates in the synaptic structures. PrPd was also observed in the granule cell layer and in the white matter. The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
http://www.prion2007.com/pdf/Prion%20Bo ... tracts.pdf
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B. Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto Superiore di Sanità, Department of Food Safety and Veterinary Public Health, Rome, Italy ([email protected]); 2 Istituto Zooprofilattico della Sardegna, Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo, Norway
Molecular variants of PrPSc are being increasingly investigated in sheep scrapie and are generally referred to as "atypical" scrapie, as opposed to "classical scrapie". Among the atypical group, Nor98 seems to be the best identified. We studied the molecular properties of Italian and Norwegian Nor98 samples by WB analysis of brain homogenates, either untreated, digested with different concentrations of proteinase K, or subjected to enzymatic deglycosylation. The identity of PrP fragments was inferred by means of antibodies spanning the full PrP sequence. We found that undigested brain homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11), truncated at both the C-terminus and the N-terminus, and not N-glycosylated. After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11. Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at the highest concentrations, similarly to PrP27-30 associated with classical scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment of 17 kDa with the same properties of PrP11, that was tentatively identified as a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in 2% sodium laurylsorcosine and is mainly produced from detergentsoluble, full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a sample with molecular and pathological properties consistent with Nor98 showed plaque-like deposits of PrPSc in the thalamus when the brain was analysed by PrPSc immunohistochemistry. Taken together, our results show that the distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids ~ 90-155. This fragment is produced by successive N-terminal and C-terminal cleavages from a full-length and largely detergent-soluble PrPSc, is produced in vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
http://www.neuroprion.com/pdf_docs/conf ... t_book.pdf
Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
Edited by Stanley B. Prusiner, University of California, San Francisco, CA, and approved September 12, 2005 (received for review March 21, 2005)
http://www.pnas.org/cgi/content/abstract/0502296102v1
snip...
Saturday, May 2, 2009
APHIS AND WHO PLAN TO EXEMPT THE ATYPICAL SCRAPIE NOR-98 FROM REGULATIONS AT MEETING THIS MONTH
http://nor-98.blogspot.com/2009/05/aphi ... pical.html
USDA's Deputy Secretary Talks with Sheep Producers
May 1, 2009 - "Life in rural America is intimately integrated with production agriculture," said Kathleen Merrigan, deputy secretary for the U.S. Department of Agriculture (USDA), when she addressed the more than 50 sheep producers from around the country who were in Washington, D.C., this week. "I am very interested in looking for new ways for farmers to market their products and for them to grab a little more of the food dollar. The connection between the food that consumers eat and the farms that the food is grown on must be closer, and I look forward to working with producers to affect that."
snip...
According to Jere Dick, DVM, associate deputy administrator and chief of field operations for the Animal and Plant Health Inspection Service (APHIS), "We anticipate discussions and hopefully revisions of the scrapie chapter at the World Organization for Animal Health meeting this month. The revisions will likely exclude Nor-98 like scrapie from classical scrapie regulations. If this is done, APHIS will be able to exempt flocks with Nor-98 like scrapie cases, should they occur, from extensive flock depopulation actions."
snip...end
http://sheepusa.org/?page=site/newsande ... cf744f349a
snip...
Nor98-like Scrapie in the United States of America
was presented by Drs. Christina M. Loiacono, S. Mark Hall, and Bruce V. Thomsen, National Veterinary Services Laboratory, USDA-APHIS-VS.
This paper describes the first six sheep diagnosed with Nor98-like disease in the United States and serves to acknowledge the increased efforts of diagnosticians and the USDA program to control and eradicate scrapie disease. Classical scrapie, a fatal neurodegenerative disease affecting the central nervous system of sheep and goats, is among a number of diseases classified as transmissible spongiform encephalopathies (TSEs). Recently, a distinct strain of scrapie was diagnosed in sheep in Norway1 and has been identified in numerous countries of the European Union (EU). The disease has been identified, among other names, as Nor98 or Nor98-like scrapie. Distinctions between classical scrapie and Nor98-like scrapie are made based on signalment, clinical signs, histopathology and immunodiagnostic results. In the past, the classical scrapie disease was confirmed by examination of the brain tissue for a triad of histopathological signs - vacuolation, loss of neurons and gliosis - and, more recently, by immunohistochemical (IHC) or biochemical detection of abnormal prion protein (PrPSc) in the brain, or lymphoid tissues. In the case of Nor98-like scrapie there is generally little or no vacuolation in the brain and, to date, no lymphoid accumulation of PrPSc has been detected. Classical scrapie typically has the most intense PrPSc immunostaining at the obex (motor nucleus of the vagus), while this area is spared in Nor98-like scrapie. Alternatively, Nor98-like scrapie consistently has PrPSc immunostaining in the spinal nucleus of the trigeminal nerve and variable, but often an intense immunostaining for PrPSc in the cerebellum. Thus the diagnosis of Nor98 and Nor98-like disease can be based on immunohistochemistry identifying abnormal prion protein in regions of the brain not typically associated with classical scrapie. Additionally there is a distinct diagnostic western blot pattern for Nor98 and Nor-98 like disease consisting of three or more protein bands with the unglycosylated band being less than 15 kd, compared to classical scrapie in which the unglycosylated band is greater than 15 kd. Nor98 and Nor-98 like disease is associated with older sheep, usually greater than four years of age, while sheep in the range of three to five years of age are more commonly affected by classical scrapie. Clinical signs are uncommon with Nor98 and Nor98-like disease but when present most often include ataxia without pruritis. Genotypes known to provide sheep with resistance to classical scrapie are not spared from Nor98 and Nor98-like disease.
The six U.S. cases had no clinical signs reported. Three cases were detected during slaughter surveillance, two were detected as a result of classical scrapie being found in the flock, one found during testing associated with diagnostic necropsy. Five of the 6 cases had genotypes that are susceptible to classical scrapie and one was AARR. Only one Nor98-like scrapie case was found per flock.
1. Benestad SL, Sarradin P, Thu B, Schönheit J, Tranulis MA, Bratberg B., Cases of scrapie with unusual features in Norway and designation of a new type, Nor98. Vet. Rec.
http://www.usaha.org/committees/reports ... r-2008.pdf
http://www.sheepusa.org/index.phtml?pag ... adff9d89bc
http://www.sheepusa.org/index.phtml?pag ... 42526bd9ee
http://www.animalagriculture.org/Procee ... herine.pdf
NOW, if there have been more of the Nor-98 documented to date, know one would know since NO MAP for the Nor-98 total cases in the USA is posted on the USDA/APHIS scrapie maps monthly report. ...TSS
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form of scrapie was first described in Norway in 1998. Several features of Nor98 were shown to be different from classical scrapie including the distribution of disease associated prion protein (PrPd) accumulation in the brain. The cerebellum is generally the most affected brain area in Nor98. The study here presented aimed at adding information on the neuropathology in the cerebellum of Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A panel of histochemical and immunohistochemical (IHC) stainings such as IHC for PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers for phagocytic cells were conducted. The type of histological lesions and tissue reactions were evaluated. The types of PrPd deposition were characterized. The cerebellar cortex was regularly affected, even though there was a variation in the severity of the lesions from case to case. Neuropil vacuolation was more marked in the molecular layer, but affected also the granular cell layer. There was a loss of granule cells. Punctate deposition of PrPd was characteristic. It was morphologically and in distribution identical with that of synaptophysin, suggesting that PrPd accumulates in the synaptic structures. PrPd was also observed in the granule cell layer and in the white matter. The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
http://www.prion2007.com/pdf/Prion%20Bo ... tracts.pdf
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B. Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto Superiore di Sanità, Department of Food Safety and Veterinary Public Health, Rome, Italy ([email protected]); 2 Istituto Zooprofilattico della Sardegna, Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo, Norway
Molecular variants of PrPSc are being increasingly investigated in sheep scrapie and are generally referred to as "atypical" scrapie, as opposed to "classical scrapie". Among the atypical group, Nor98 seems to be the best identified. We studied the molecular properties of Italian and Norwegian Nor98 samples by WB analysis of brain homogenates, either untreated, digested with different concentrations of proteinase K, or subjected to enzymatic deglycosylation. The identity of PrP fragments was inferred by means of antibodies spanning the full PrP sequence. We found that undigested brain homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11), truncated at both the C-terminus and the N-terminus, and not N-glycosylated. After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11. Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at the highest concentrations, similarly to PrP27-30 associated with classical scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment of 17 kDa with the same properties of PrP11, that was tentatively identified as a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in 2% sodium laurylsorcosine and is mainly produced from detergentsoluble, full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a sample with molecular and pathological properties consistent with Nor98 showed plaque-like deposits of PrPSc in the thalamus when the brain was analysed by PrPSc immunohistochemistry. Taken together, our results show that the distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids ~ 90-155. This fragment is produced by successive N-terminal and C-terminal cleavages from a full-length and largely detergent-soluble PrPSc, is produced in vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
http://www.neuroprion.com/pdf_docs/conf ... t_book.pdf
Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
Edited by Stanley B. Prusiner, University of California, San Francisco, CA, and approved September 12, 2005 (received for review March 21, 2005)
http://www.pnas.org/cgi/content/abstract/0502296102v1
snip...
Saturday, May 2, 2009
APHIS AND WHO PLAN TO EXEMPT THE ATYPICAL SCRAPIE NOR-98 FROM REGULATIONS AT MEETING THIS MONTH
http://nor-98.blogspot.com/2009/05/aphi ... pical.html
