The Zoonotic Potential of Chronic Wasting Disease—A Review

Prion diseases are transmissible neurodegenerative disorders that affect humans and ruminant species consumed by humans. Ruminant prion diseases include bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep and goats and chronic wasting disease (CWD) in cervids. In 1996, prions causing BSE were identified as the cause of a new prion disease in humans; variant Creutzfeldt-Jakob disease (vCJD). This sparked a food safety crisis and unprecedented protective measures to reduce human exposure to livestock prions. CWD continues to spread in North America, and now affects free-ranging and/or farmed cervids in 30 US states and four Canadian provinces. The recent discovery in Europe of previously unrecognized CWD strains has further heightened concerns about CWD as a food pathogen. The escalating CWD prevalence in enzootic areas and its appearance in a new species (reindeer) and new geographical locations, increase human exposure and the risk of CWD strain adaptation to humans. No cases of human prion disease caused by CWD have been recorded, and most experimental data suggest that the zoonotic risk of CWD is very low. However, the understanding of these diseases is still incomplete (e.g., origin, transmission properties and ecology), suggesting that precautionary measures should be implemented to minimize human exposure.publishedVersio

Assessment of risk of introduction of Echinococcus multilocularis to mainland Norway

Source at https://vkm.no/In the light of the recent findings of the tapeworm Echinococcus multilocularis (EM) in four red foxes from three different locations in Sweden, the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen; VKM), Panel of Biological Hazards (Faggruppe hygiene og smittestoffer) took the initiative to undertake a risk assessment regarding the probability of this parasite being introduced to mainland Norway and thus becoming a threat to public health in the country.Med bakgrunn i funnet av bendelorm Echinococcus multilocularis (EM) i fire rødrev fra tre forskjellige steder i Sverige, har VKM ved Faggruppe hygiene og smittestoffer tatt initiativ til å foreta en vurdering av sannsynligheten for at EM kan bli introdusert til fastlands Norge og sannsynligheten for at mennesker i så fall også kan bli smittet

CWD in Norway. Opinion of the Panel on Biological Hazards of the Norwegian Scientific Committee for Food Safety

The Norwegian Food Safety Authority (NFSA) and Norwegian Environmental Authority (NEA) asked the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) for an opinion on factors associated with the introduction of Chronic Wasting Disease (CWD) to Norway. VKM appointed a working group consisting of two members of the Panel on Biological Hazards, one member of Panel on Animal Health and Welfare, and two external experts to prepare the answer to the questions. The Panel on Biological Hazards has reviewed and revised the draft prepared by the working group and approved the opinion. CWD was diagnosed in March 2016 in a wild reindeer (Rangifer tarandus) from the Nordfjella mountain area in Norway and in May and June in two mooses (Alces alces) in Selbu in South Trøndelag County, approximately 300 km north from the first case. There is currently no information to determine the origin(s) of CWD agents in Norway. However, the sporadic or genetic (somatic mutation) occurrence of prion disease in cervids cannot be excluded, nor can introduction from North America or other countries. Furthermore, there is no evidence that it has not been circulating at low levels in the Norwegian cervid populations for years, but has not previously been identified. In this scientific opinion, information on prion diseases in general, and CWD in particular, is presented in the light of experiences with this disease in North America. Prions are among the most resilient pathogens known and dissemination of prions into ecosystems is likely to result in long-term problems. Prions bind strongly to soil and remain infectious. In CWD, prions are present in most peripheral organs and also shed into the environment via saliva, faeces, and urine, as well as with the placenta. CWD transmits easily among cervids, either through direct contact, or indirectly via the environment. Migration of animals is relevant for the spread between areas. Strain diversification might occur in CWD and may influence transmission properties of the agents. Clinical signs of CWD are non-specific and do not alone enable confirmation of the diagnosis. Analysis of tissue from the brainstem at the level of the obex by approved methods is necessary for diagnosis of CWD. Prion infectivity is assessed by bioassays, often involving transgenic mice. In vitro conversion assays, like protein misfolding cyclic amplification (PMCA), provide sensitive quantification of converting activity, which is a good approximation of infectivity. Genetic variation (polymorphisms) in the gene that encodes PrP (PRNP) can modulate sensitivity towards CWD. The level of such genetic variation in Norwegian wild and semi- domesticated cervids is currently unknown. Cattle and sheep are at very low risk of developing CWD and it is highly unlikely that prion diseases in sheep or cattle are the origin of CWD. VKM Report 2016: 26 6 Although transmission of CWD to humans has never been known to occur, and animals other than cervids have not been found to be infected, indicating a species barrier, this possibility cannot be excluded. Thus, measures for reduction of human exposure are recommended. Taking into account uncertainties regarding the plasticity of the CWD agents and the lack of transmission data from the Norwegian isolates, this scientific opinion considers the zoonotic risk of CWD to be very low.publishedVersio

CWD in Norway

Source at https://vkm.no/The Norwegian Food Safety Authority (NFSA) and Norwegian Environmental Authority (NEA) asked the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) for an opinion on factors associated with the introduction of Chronic Wasting Disease (CWD) to Norway. VKM appointed a working group consisting of two members of the Panel on Biological Hazards, one member of Panel on Animal Health and Welfare, and two external experts to prepare the answer to the questions. The Panel on Biological Hazards has reviewed and revised the draft prepared by the working group and approved the opinion.Mattilsynet og Miljødirektoratet har bedt Vitenskapskomitéen for mattrygghet (VKM) om å besvare spørsmål knyttet til mattrygghet og dyrehelse etter at den uhelbredelige sykdommen Chronic Wasting Disease (CWD) nylig ble påvist hos en villrein og senere hos to elger i Norge. VKM nedsatte en arbeidsgruppe bestående av to medlemmer fra Faggruppen for hygiene og smittestoffer, ett medlem fra Faggruppen for dyrehelse- og velferd samt to eksterne eksperter, for å utarbeide en vurdering knyttet til de stilte spørsmålene. Faggruppen for hygiene og smittestoffer har lest utkast til rapporten og godkjent vurderingen

Impaired NDRG1 functions in Schwann cells cause demyelinating neuropathy in a dog model of Charcot-Marie-Tooth type 4D

Mutations in the N-myc downstream-regulated gene 1 (NDRG1) cause degenerative polyneuropathy in ways that are poorly understood. We have investigated Alaskan Malamute dogs with neuropathy caused by a missense mutation in NDRG1. In affected animals, nerve levels of NDRG1 protein were reduced by more than 70% (p < 0.03). Nerve fibers were thinly myelinated, loss of large myelinated fibers was pronounced and teased fiber preparations showed both demyelination and remyelination. Inclusions of filamentous material containing actin were present in adaxonal Schwann cell cytoplasm and Schmidt-Lanterman clefts. This condition strongly resembles the human Charcot-MarieTooth type 4D. However, the focally folded myelin with adaxonal infoldings segregating the axon found in this study are ultrastructural changes not described in the human disease. Furthermore, lipidomic analysis revealed a profound loss of peripheral nerve lipids. Our data suggest that the low levels of mutant NDRG1 is insufficient to support Schwann cells in maintaining myelin homeostasis. (C) 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license

Oppdatert kunnskap om det zoonotiske potensialet av skrantesjuke ved håndtering av slakt og konsum av kjøtt. Vitenskapelig uttalelse fra faggruppen for hygiene og smittestoffer i Vitenskapskomiteen for mat og miljø

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Risk assessment on use of Lactobacillus rhamnosus (LGG) as an ingredient in infant formula and baby foods (II)

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Monitoring of chronic wasting disease (CWD) (IV)

The European Commission requested an analysis of the Chronic Wasting Disease (CWD) monitoring programme in Norway, Sweden, Finland, Iceland, Estonia, Latvia, Lithuania and Poland (9 January 2017–28 February 2022). Thirteen cases were detected in reindeer, 15 in moose and 3 in red deer. They showed two phenotypes, distinguished by the presence or absence of detectable disease-associated normal cellular prion protein (PrP) in lymphoreticular tissues. CWD was detected for the first time in Finland, Sweden and in other areas of Norway. In countries where the disease was not detected, the evidence was insufficient to rule out its presence altogether. Where cases were detected, the prevalence was below 1%. The data also suggest that the high-risk target groups for surveillance should be revised, and ‘road kill’ removed. Data show that, in addition to differences in age and sex, there are differences in the prion protein gene (PRNP) genotypes between positive and negative wild reindeer. A stepwise framework has been proposed with expanded minimum background surveillance to be implemented in European countries with relevant cervid species. Additional surveillance may include ad hoc surveys for four different objectives, specific to countries with/without cases, focusing on parallel testing of obex and lymph nodes from adult cervids in high-risk target groups, sustained over time, using sampling units and a data-driven design prevalence. Criteria for assessing the probability of CWD presence have been outlined, based on the definition of the geographical area, an annual assessment of risk of introduction, sustained minimum background surveillance, training and engagement of stakeholders and a surveillance programme based on data-driven parameters. All positive cases should be genotyped. Sample sizes for negative samples have been proposed to detect and estimate the frequency of PRNP polymorphisms. Double-strand sequencing of the entire PRNP open reading frame should be undertaken for all selected samples, with data collated in a centralised collection system at EU level.info:eu-repo/semantics/publishedVersio

Oppdatert kunnskap om det zoonotiske potensialet av skrantesjuke ved håndtering av slakt og konsum av kjøtt. Vitenskapelig uttalelse fra faggruppen for hygiene og smittestoffer i Vitenskapskomiteen for mat og miljø

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Risk assessment on use of Lactobacillus rhamnosus (LGG) as an ingredient in infant formula and baby foods (II)

Source at https://vkm.no/On 10. March 2006 , The Norwegian Food Safety Authority (Mattilsynet) decided that, on the basis of VKM’s previous risk assessment (2005), Nutramigen 1 with Lactobacillus rhamnosus GG (LGG) could not be marketed in Norway as medical foods for infants (0-4 months). In addition, The Norwegian Food Safety Authority (Mattilsynet) decided (08. November 2006) to withdraw permission for marketing ofNutramigen 2 with LGG, which is a milk supplement for infants aged between 4 and 6 months, with cow’s milk and soy protein allergy. On 13. December 2006, Mead Johnson Nutritionals appealed against this decision from The Norwegian Food SafetyAuthority (Mattilsynet). The Norwegian Food Safety Authority forwarded the appeal from the companies, asked the VKM Panel on biological hazards and the VKM Panel on nutrition, dietetic products, novel food and allergy, for a new risk assessment including the new data provided in the appeal.Basert på VKMs tidligere risikovurdering fra 2005, bestemte Mattilsynet 10. mars 2006 atNutramigen 1 med LGG ikke kunne markedsføres som næringsmiddel til spesielle medisinske formål (0-4 måneder) i Norge. I tillegg trakk Mattilsynet tilbake tillatelsen (08. november, 2006) til å markedsføre Nutramigen 2 med LGG, som er en melkeerstatning for spedbarn mellom fire og seks måneder som er allergiske mot kumelk og soyaproteiner. Den 13. desember 2006 Mead Johnson Nutritionals på vedtaket fra Mattilsynet. Mattilsynet videresendte klagen fra selskapene og ba VKMs faggrupper for hygiene og smittestoffer samt ernæring, dietetiske produkter, ny mat og allergi om å foreta en ny risikovurdering basert på nye data som er lagt frem i forbindelse med klagen