Scrapie TSE Prion EU Update
Scrapie TSE Prion EU Update
Spain Scrapie Outbreak
Navarra registra el primer foco de scrapie de 2023 en España
El Ministerio de Agricultura ha notificado un foco de tembladera en una explotación de ovejas en el municipio de Ultzama
Itziar Gómez López, consejera de Desarrollo Rural y Medio Ambiente de Navarra.
Itziar Gómez López, consejera de Desarrollo Rural y Medio Ambiente de Navarra.
Francisco Ramón López - 18-04-2023 - 10:21 H - 2 min.
Este martes 18 de abril, el Ministerio de Agricultura, Pesca y Alimentación (MAPA) ha notificado un foco de scrapie, también conocida como tembladera o prurigo lumbar, en una explotación de ovejas en el municipio de Ultzama, en Navarra.
Se trata del primer foco de 2023 y según los datos del MAPA se ha producido en una explotación de 132 animales, aunque solo ha afectado a uno. En 2022 se notificaron un total de 27 focos. Entre los años 2000 y 2021 se han detectado un total de 598 focos, sin un descenso significativo.
La tembladera es un proceso neurodegenerativo progresivo que afecta a ovejas y cabras, que se clasifica como una encefalopatía espongiforme transmisible (EET) o enfermedad causada por priones.
Se divide en casos atípicos y clásicos. En lo referente a los casos atípicos de tembladera aparecen de forma natural y esporádica, mientras que la transmisión de los casos clásicos está influenciada por transmisión de la madre a su descendencia inmediatamente después del parto.
Además, se puede infectar a otros neonatos susceptibles expuestos a los fluidos expulsados durante el parto o tejidos de un animal infectado. En adultos la infección es mucho menos común y en humanos no se ha demostrado que se pueda transmitir, como sí que ocurría con la ‘enfermedad de las vacas locas’.
Según los datos del último informe de encefalopatías espongiformes transmisibles, 10 de los focos de 2021 fueron de cepas clásicas y 8 de atípicas.
English
Navarra records the first outbreak of scrapie in 2023 in Spain
The Ministry of Agriculture has notified an outbreak of scrapie on a sheep farm in the municipality of Ultzama
Itziar Gómez López, Minister of Rural Development and Environment of Navarra.
Itziar Gómez López, Minister of Rural Development and Environment of Navarra.
Francisco Ramón López - 04-18-2023 - 10:21 a.m. - 2 min.
This Tuesday, April 18, the Ministry of Agriculture, Fisheries and Food (MAPA) has notified an outbreak of scrapie, also known as scrapie or scrapie, on a sheep farm in the municipality of Ultzama, in Navarra.
This is the first outbreak of 2023 and according to the MAPA data it has occurred on a farm with 132 animals, although it has only affected one. In 2022, a total of 27 outbreaks were reported. Between the years 2000 and 2021, a total of 598 outbreaks have been detected, without a significant decrease.
Scrapie is a progressive neurodegenerative process affecting sheep and goats, classified as a transmissible spongiform encephalopathy (TSE) or prion disease.
It is divided into atypical and classic cases. Regarding the atypical cases of scrapie, they appear naturally and sporadically, while the transmission of classic cases is influenced by transmission from the mother to her offspring immediately after delivery.
In addition, other susceptible neonates exposed to fluids expelled during delivery or tissues from an infected animal can become infected. In adults, the infection is much less common and in humans it has not been shown that it can be transmitted, as it did with 'mad cow disease'.
According to the data from the latest report on transmissible spongiform encephalopathies, 10 of the outbreaks in 2021 were from classic strains and 8 from atypical strains.
Active TSE surveillance in Great Britain and Northern Ireland
EFSA Journal 2022;20(11):7655
DOI
KEYWORDS TSE, BSE, CWD, scrapie, classical, atypical, surveillance
ON REQUEST FROM European Commission QUESTION NUMBER EFSA‐Q‐2021‐00765
CONTACT zoonoses@efsa.europa.eu
Abstract
This report presents the results of surveillance on transmissible spongiform encephalopathies (TSE) in cattle, sheep, goats, cervids and other species, and genotyping in sheep and goats, carried out in 2021 by 27 Member States (MS, EU27), the United Kingdom (in respect of Northern Ireland) (XI), and eight other non‐EU reporting countries:
Bosnia and Herzegovina, Iceland, Montenegro, North Macedonia, Norway, Serbia, Switzerland and Turkey.
In total, 1,021,252 cattle were tested by EU27 and XI (−9%, compared with 2020 when data from the United Kingdom were not restricted to Northern Ireland), and 66,121 cattle by eight non‐EU reporting countries, with two cases of H‐BSE in France and Spain, and four L‐BSE in France (2), Germany and Spain.
In total, 311,174 sheep and 118,457 goats were tested in the EU27 and XI (−6.4% and −1.8%, respectively, compared to 2020 when data from the whole United Kingdom were considered).
In sheep, 551 cases of scrapie were reported by 17 MS and XI:
448 classical scrapie (CS) by six MS [80 index cases (IC) with genotypes of susceptible groups in 97% of the cases], 103 atypical scrapie (AS) (96 IC) by 13 MS and XI.
In the other non‐EU reporting countries, 27,594 sheep were tested with 55 CS and 1 AS in Iceland and 8 AS in Norway.
Ovine random genotyping was reported by nine MS and genotypes of susceptible groups accounted for 7.9%.
In goats, 224 cases of scrapie were reported by six EU MS:
219 CS (30 IC) by six MS, and five AS (5 IC) by three MS.
In total, 5,854 cervids were tested for chronic wasting disease by eight MS; all resulted negative.
Norway tested 21,670 cervids with two moose and one red deer positive.
In total, 149 animals from four other species tested negative in Finland and Turkey.
© European Food Safety Authority
OPINION article
Front. Vet. Sci., 29 September 2020
Sec. Veterinary Infectious Diseases
Volume 7 - 2020 | https://doi.org/10.3389/fvets.2020.581969
The Epidemiology, Diagnosis and Prevention of Infectious Diseases in Livestock
Scrapie Control in EU Goat Population: Has the Last Gap Been Overcome?
Sergio Migliore*, Roberto Puleio and Guido Ruggero Loria
Istituto Zooprofilattico Sperimentale Della Sicilia “A. Mirri”, Palermo, Italy
Introduction
Scrapie is a fatal, neurodegenerative disease that affects sheep and goat worldwide, belonging to the group of transmissible spongiform encephalopathies (TSEs).
Since 2002, Member States (MS) of European Union (EU) have implemented active surveillance to control the risk of scrapie. The EU scrapie eradication policy is mainly aimed to eradicate classical scrapie. The choice of population groups and sample sizes have evolved in the years, as well as the eradication measures and control of disease (selective culling, movement restrictions, reinforced surveillance measures, etc.). In this context, over the past two decades, breeding programs to increase the frequency of the resistance-associated ARR allele in sheep populations have been introduced to minimize TSE risk in MS, but there was not a regulatory effort in adoption of analogous measures for goats. However, scientific knowledge related to scrapie resistance associated with goat PRNP gene polymorphisms has considerably expanded in the last 10 years.
Classical scrapie is considered endemic in many MS. Since its publication, the only measures applicable for TSE control in goat contained in Regulation (EC) No 999/2001 obliged farmers to provide a complete culling of whole flock, with great economic loss and serious concerns for the risk of extinction of endangered breeds. However, over the years, additional measures have been introduced such as monitoring of the infected herd without the obligation of total culling and the possibility of reintroducing goats with unknown genotype after biosafety practices. Nevertheless, these measures could allow the goat population to become the main reservoir of scrapie, affecting the disease eradication program in small ruminant population.
Following a request from the European Commission (EC), the European Food Safety Authority (EFSA) was asked to deliver scientific opinions on the scrapie situation in EU to evaluate the introduction of breeding policies in goats. From 2014, EFSA advised to promote selection and introduction of resistant bucks in EU caprine population (1). More recently, in 2017, based on the latest scientific evidence, EFSA concluded that breeding programs for scrapie resistance in goats should be implemented in MS, taking particular attention to potential negative effects of extinction in rare and endangered breeds (2).
With Regulation (EC) No 2020/772 of June 11, 2020, amending Regulation (EC) No 999/2001, EC laid down new approaches as regards eradication measures for TSEs in goats and in endangered breeds. In this context, the authors discuss advantages and critical points related to the different control measures introduced by EU regulations during the last two decades.
State of the Art
Legislative Basis
Regulation (EC) No 999/2001 establishes rules for the prevention, control, and eradication of certain TSEs, including scrapie in small ruminants. This Regulation dates back to 2001 and, after many subsequent amendments, is still in force today.
In 2003, Regulation (EC) No 260/2003 revised the requirements for eradication measures in case of the detection of TSE in a farm by selective culling of susceptible sheep and by requiring the implementation of measures to increase TSE resistance in the outbreak. Simultaneously, decision 2003/100 (EC) laid down requirements for the establishment of breeding programs for resistance to TSE in sheep, aimed to increase the level of alleles associated with resistance (ARR) and decreasing the frequency of alleles associated with susceptibility (VRQ) in EU sheep population. Commission Regulation (EC) No 1923/20065 and No 727/2007 then integrated the breeding program requirements into Regulation (EC) No 999/2001. In 2006, EFSA confirmed the efficacy of breeding program for TSE resistance in sheep (3).
More recently, on June 11, 2020, Regulation (EC) No 2020/772 amended Annexes I, VII, and VIII to Regulation (EC) No 999/2001 introducing the possibility for the MS to limit slaughtering/culling and destruction to goats which are genetically susceptible to classical scrapie. In addition, the definition of “endangered breed” of Regulation (EU) 2016/1012 replaced the expression of “local breed in danger of being lost to farming” as laid down in Regulation (EU) No 807/2014 (4).
Scrapie in EU Goats
Classical scrapie shows similar epidemiological features in sheep and goats and the involvement of both species in outbreaks is common. Even if the incidence in goats is much lower than in sheep, milk and placenta of infected goats may serve as sources of infection to sheep (5, 6). Scrapie in goat was described for the first time in 1942 (4); since then, clinical cases have been recorded throughout Europe. Animal movements between herds and environmental contamination play relevant roles as risk factors.
In 2019, a total of 325,386 sheep and 138,128 goats were tested in EU. In sheep, 821 cases of classical scrapie were detected in seven MS, whereas 517 cases were reported in goats in seven MS (7). Scrapie in goat is considered endemic in the EU countries with the largest caprine populations with more than 10,500 cases from 2002 to 2017. Between 2002 and 2015, classical scrapie was detected in 10 MS with 2.4 cases out of 10,000 tested heads. In this prevalence study, Cyprus was excluded due to an epidemic over the last 10 years (2).
Genetic Basis
In the last two decades, an extensive review of literature was conducted to identify relevant alleles of goat PRNP to which a breeding program could be based. These studies were conducted within different MS and goat breeds. A considerable dataset has been produced for the following alleles: S127, M142, R143, D145, D146, S146, H154, Q211, and K222. Among them, K222, D146, and S146 alleles confer higher genetic resistance to classical scrapie strains circulating in the EU goat population (2). In 2017, based on a combination of the “weight of evidence” and the “strength of resistance,” EFSA provided a ranking of resistance to classical scrapie, as follows: K222 > D146 = S146 > Q211 = H154 = M142 > S127 = H143 > wild type (2).
Goat Breeding in EU
Goat farming plays an important socioeconomic role in several countries, particularly where there are hills and mountains, and remote, marginal, and even semi-arid areas (8, 9). Europe is the continent with the widest caprine biodiversity with 187 goat breeds, which is 33% of the goat breeds acknowledged worldwide (10). In this context, there are breeds with large population sizes, cosmopolitan and often characterized by a high production, and breeds with small population sizes not yet subjected to conservation programs because of their remoteness or because they are less competitive in terms of production than other selected breeds (9). Such different scenarios obviously have required a different scrapie control strategy.
Discussion
In 2017, EFSA, based on prolonged field experience and experimental studies, concluded that the K222, D146, and S146 variants confer genetic resistance to the classical scrapie strain circulating in the EU goat population (2). EFSA highlighted that the protective effect of K222 is greater than D146 and S146 variants and of ARR allele in sheep, when the 2002 Scientific Steering Committee opinion was published (2). In this regard, a substantial difference between sheep and goats in the new Regulation (EC) No 2020/772 still remains. In sheep, the ARR/ARR homozygous genotype in reproductive males is an essential requirement, whereas in goats, heterozygosity for at least one of K222 and D/S146 alleles is sufficient to avoid the stamping out. It should be remembered that heterozygous variants Q222K and N146S/D in goats do not confer full protection against classical scrapie as reported in natural outbreaks in Greece (11) and in Cyprus (12). In addition, the subsequent restocking of outbreak without genotype consideration after biosafety practices is a considerable risk. These are critical points whose efficacy will be assessed in the future.
The EFSA opinion also highlights that a high selective pressure in some breeds with a low frequency of resistant variants would likely have an adverse effect on genetic diversity and that each MS should be able to design its own genetic selection strategy depending on the breed concerned.
Estimating the frequency of candidate alleles is a preliminary step in understanding the feasibility of a breeding program. Several investigations on goat PRNP were performed in MS in recent years, and some breed-related differences emerged (Table 1). Higher frequency (>24.5%) of 146D or S variants was described in cosmopolitan Boer goat in Great Britain and Netherlands (13–15) and in native Damascus and related breeds in Cyprus (16.5%) (17). A lower frequency (3%) was also described in local and crossbred in Greece (16). To date, this mutation does not seem to be widespread in other MS. In contrast, 222 K variant seems to be more common across the MS. Frequencies between 1.2 and 7.5% were described in cosmopolitan and large population size breeds such as Saanen (1.2–4%) and Alpine (6.4–7.5%) reared in Spain, Netherlands, Italy, France, and Greece (15, 16, 18–20). Very high frequency (29.5%) was described in Dutch Toggenburg in Netherlands (15). Variable frequencies were described in small size of native breeds such as local and crossbred in Greece (0.3–5.6%) (16). In Italy, where a great caprine biodiversity is present, a difference between northern and southern native breeds was described (20), with higher frequencies of 222 K in Southern breed such as Garganica (17.2%), Ionica (7.2%), southern crossbred (22.5%), Girgentana (18.7%), Rossa Mediterranea (12.7%), Argentata dell'Etna (16.3%), Aspromontana (10.3%), and Cilentana (18.2%) (20–23). Many of these breeds are considered in critical or endangered status (24) and for this reason any breeding program should consider the endangered status of each goat population to preserve the genetic variability and the biodiversity together with disease control (21).
Table 1 www.frontiersin.org TABLE 1. Breeds with S146/D146 and K222 haplotypes reported in literature and their frequencies reported in EU.
Various mutations in the PRNP in different breeds have potentially been positively selected in relation to local circulating scrapie strains originating in specific environmental conditions (25).
A recent study (26) assessed the impact of different breeding strategies in goat using a mathematical model, and it concluded that breeding programs for scrapie resistance could be implemented also in a context of so high biodiversity and also different size of the populations of goats. Nevertheless, the growth rate of resistant goats in some breeds may be slow due to the initial genetic profile not being particularly favorable inside the breed. In cosmopolitan breeds with a large population size, a breeding program in the overall population would be desirable. In contrast, in endangered breeds with a small population, a breeding program should be implemented starting from reproductive nuclei. This scheme is less expansive and protects the endangered breeds even if it takes longer to reach the expected results.
As well as goat breeds, a breeding program for scrapie resistance should consider the particular situation of each MS in terms of the presence of resistant alleles and their relative frequency. For example, in Greece, which has one of the largest goat populations in Europe, a goat-scrapie resistance program targeting the Q211, S146, and K222 alleles was designed (27), whereas in Italy, pilot projects selected positively a singular variant K222.
Although there is a strong interest in disease control among goat farmers in the Northern MS, breeding for resistance is often compromised by the low frequency of resistant alleles. By contrast, in Southern MS where a satisfying frequency of resistant alleles is present, goat farming is mainly related to pastoralism and in several cases there is a lack of interest in starting genetic programs. For this reason, to be successful, new regulations have to consider engaging farmers' cooperation by appropriate risk communication and involving them in the genetic program as well as providing an adequate financial support for goat genotyping.
Regulation (EC) No 2020/772 laid down an alternative tool for scrapie control in EU goat population. It particularly recognized the genetic resistance to classical scrapie in goats carrying at least one of the most recognized alleles (K222, D146, and S146) and preserving them from culling in the case of outbreak. In addition, the new regulation introduces possible derogation measures for endangered breeds according to Regulation (EU) 2016/1012. This new measure will finally strengthen the control of TSEs in small ruminants in the EU and will also have beneficial effects on farming system and for the conservation of goat breed biodiversity.
''In 2019, a total of 325,386 sheep and 138,128 goats were tested in EU. In sheep, 821 cases of classical scrapie were detected in seven MS, whereas 517 cases were reported in goats in seven MS (7). Scrapie in goat is considered endemic in the EU countries with the largest caprine populations with more than 10,500 cases from 2002 to 2017. Between 2002 and 2015, classical scrapie was detected in 10 MS with 2.4 cases out of 10,000 tested heads. In this prevalence study, Cyprus was excluded due to an epidemic over the last 10 years (2).''
atypical Scrapie
***> AS is considered more likely (subjective probability range 50–66%) that AS is a non-contagious, rather than a contagious, disease.
SNIP...SEE;
THURSDAY, JULY 8, 2021
EFSA Scientific report on the analysis of the 2‐year compulsory intensified monitoring of atypical scrapie
***> AS is considered more likely (subjective probability range 50–66%) that AS is a non-contagious, rather than a contagious, disease.
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies
Location: Virus and Prion Research
Title: Transmission of the atypical/nor98 scrapie agent to suffolk sheep with VRQ/ARQ, ARQ/ARQ, and ARQ/ARR genotypes
Author
item Cassmann, Eric
item MAMMADOVA, JAJIBA - Orise Fellow
item BENESTAD, SYLVIE - Norwegian Veterinary Institute
item MOORE, SARA JO - Orise Fellow
item Greenlee, Justin
Submitted to: PLoS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2021
Publication Date: 2/11/2021
Citation: Cassmann, E.D., Mammadova, J., Benestad, S., Moore, S., Greenlee, J.J. 2021. Transmission of the atypical/nor98 scrapie agent to suffolk sheep with VRQ/ARQ, ARQ/ARQ, and ARQ/ARR genotypes. PLoS ONE. 16(2). Article e0246503. https://doi.org/10.1371/journal.pone.0246503.
Interpretive Summary: Atypical scrapie is a prion disease that affects sheep. Unlike classical scrapie, atypical scrapie is thought to occur spontaneously, and it is unlikely to transmit between sheep under natural conditions. Another notable distinction between classical and atypical scrapie is the prion protein genotype of afflicted sheep and the locations in the brain where misfolded prions accumulate. Atypical scrapie generally occurs in sheep that are resistant to classical scrapie. Misfolded prions are predominantly found in the cerebellum for atypical scrapie and not in the brainstem as seen with classical scrapie. Atypical scrapie is a relevant disease because of its potential association with other prion diseases. Some research has shown that the atypical scrapie agent can undergo a transformation of disease forms that makes it appear like classical scrapie or classical bovine spongiform encephalopathy (mad cow disease). Therefore, atypical scrapie is thought to be a possible source for these prion diseases. We investigated the transmission of the atypical scrapie agent to sheep with three different prion protein genotypes. A diagnosis of atypical scrapie was made in all three genotypes of sheep. Misfolded prion protein was detected earliest in the cerebellum and the retina. This is the first report describing the early accumulation of misfolded prions in the retina of sheep with atypical scrapie. Understanding where misfolded prions accumulate in cases of atypical scrapie can lead to better detection earlier in the disease. Furthermore, the materials derived from this experiment will aid in investigating origins of other prion diseases.
Technical Abstract: Scrapie is a transmissible spongiform encephalopathy that occurs in sheep. Atypical/Nor98 scrapie occurs in sheep with that tend to be resistant to classical scrapie and it is thought to occur spontaneously. The purpose of this study was to test the transmission of the Atypical/Nor98 scrapie agent in three genotypes of Suffolk sheep and characterize the distribution of misfolded prion protein (PrPSc). Ten sheep were intracranially inoculated with brain homogenate from a sheep with Atypical/Nor98 scrapie. All sheep with the ARQ/ARQ and ARQ/ARR genotypes developed Atypical/Nor98 scrapie confirmed by immunohistochemistry, and one (1/3) sheep with the VRQ/ARQ genotype had detectable PrPSc consistent with Atypical/Nor98 scrapie at the experimental endpoint of 8 years. Sheep with mild early accumulations of PrPSc in the cerebellum had concomitant retinal PrPSc. Accordingly, large amounts of retinal PrPSc were identified in clinically affected sheep and sheep with dense accumulations of PrPSc in the cerebellum.
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases).
Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
==============
PRION 2015 CONFERENCE
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
Title: Transmission of scrapie prions to primate after an extended silent incubation period)
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
TUESDAY, APRIL 4, 2023
Iceland Reports Another Case of Scrapie
https://animalhealthreportpriontse.blogspot.com/2023/04/iceland-reports-another-case-of-scrapie.html
MONDAY, SEPTEMBER 13, 2021
New case of scrapie in Iceland Skagafjörður
THURSDAY, OCTOBER 29, 2020
OIE ICELAND, SCRAPIE
THURSDAY, JULY 09, 2020
OIE Scrapie, Portugal
FRIDAY, JANUARY 08, 2021
Canada Scrapie Flock Certification Program
TUESDAY, FEBRUARY 08, 2022
Romania Outbreaks of scrapie in two sheep farms 750 animals are affected
FRIDAY, JANUARY 20, 2023
EPIDEMIOLOGY OF SCRAPIE IN THE UNITED STATES
WEDNESDAY, FEBRUARY 03, 2021
Scrapie TSE Prion United States of America a Review February 2021 Singeltary et al
WEDNESDAY, MARCH 16, 2022
SHEEP BY-PRODUCTS AND WHAT ABOUT Scrapie TSE PrP and Potential Zoonosis?
WEDNESDAY, DECEMBER 8, 2021
Importation of Sheep, Goats, and Certain Other Ruminants AGENCY: Animal APHIA, USDA, FINAL RULE [Docket No. APHIS–2009–0095] RIN 0579–AD10
FRIDAY, DECEMBER 10, 2021
USDA APHIS National Scrapie Eradication Program October 2021 Monthly Report Fiscal Year 2022
MONDAY, NOVEMBER 29, 2021
Experimental Oronasal Transmission of Chronic Wasting Disease Agent from White-Tailed Deer to Suffolk Sheep Volume 27, Number 12—December 2021 Dispatch
FRIDAY, DECEMBER 10, 2021
Scrapie at Abattoir: Monitoring, Control, and Differential Diagnosis of Wasting Conditions during Meat Inspection
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. | 4:15 PM
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