Thursday, January 30, 2014

Evidence in Sheep for Pre-Natal Transmission of Scrapie to Lambs from Infected Mothers

Evidence in Sheep for Pre-Natal Transmission of Scrapie to Lambs from Infected Mothers

 

James D. Foster, Wilfred Goldmann, Nora Hunter*

 

The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Midlothian, Scotland, United Kingdom

 

Abstract

 

Natural scrapie transmission from infected ewes to their lambs is thought to occur by the oral route around the time of birth. However the hypothesis that scrapie transmission can also occur before birth (in utero) is not currently favoured by most researchers. As scrapie is an opportunistic infection with multiple infection routes likely to be functional in sheep, definitive evidence for or against transmission from ewe to her developing fetus has been difficult to achieve. In addition the very early literature on maternal transmission of scrapie in sheep was compromised by lack of knowledge of the role of the PRNP (prion protein) gene in control of susceptibility to scrapie. In this study we experimentally infected pregnant ewes of known PRNP genotype with a distinctive scrapie strain (SSBP/1) and looked for evidence of transmission of SSBP/1 to the offspring. The sheep were from the NPU Cheviot flock, which has endemic natural scrapie from which SSBP/1 can be differentiated on the basis of histology, genetics of disease incidence and strain typing bioassay in mice. We used embryo transfer techniques to allow sheep fetuses of scrapie-susceptible PRNP genotypes to develop in a range of scrapie-resistant and susceptible recipient mothers and challenged the recipients with SSBP/1. Scrapie clinical disease, caused by both natural scrapie and SSBP/1, occurred in the progeny but evidence (including mouse strain typing) of SSBP/1 infection was found only in lambs born to fully susceptible recipient mothers. Progeny were not protected from transmission of natural scrapie or SSBP/1 by washing of embryos to International Embryo Transfer Society standards or by caesarean derivation and complete separation from their birth mothers. Our results strongly suggest that pre-natal (in utero) transmission of scrapie may have occurred in these sheep.

 

SNIP...

 

In conclusion therefore, our study has presented evidence that suggests that transmission of scrapie can occur from the infected mother sheep to her lamb before birth, although it is almost certain not to be the only route by which a lamb can become infected. Further studies are clearly necessary in order to understand the underlying mechanisms and to be able to assess whether the very different placental structures in humans will protect babies from infection if born to CJD infected mothers. Other studies are near completion in our laboratory aimed at clarifying the rate of maternal transmission using scrapie-free sheep of New Zealand origin and therefore without the potential interference from natural scrapie. The ultimate aim of control and eradiation of scrapie infection in sheep clearly depends on understanding all the potential routes of transmission as the use of genetically resistant sheep is not always possible, especially for some rare breeds.

 

Citation: Foster JD, Goldmann W, Hunter N (2013) Evidence in Sheep for Pre-Natal Transmission of Scrapie to Lambs from Infected Mothers. PLoS ONE 8(11): e79433. doi:10.1371/journal.pone.0079433

 

Editor: Ilia V. Baskakov, University of Maryland School of Medicine, United States of America

 

Received September 11, 2013; Accepted September 19, 2013; Published November 18, 2013

 

Copyright: 2013 Foster et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

 

Funding: The project was funded by Defra (UK Department for the Environment, Food and Rural Affairs) Grant number SE1823 (www.gov.co.uk/defra) with core support funding to the Institute for Animal Health from BBSRC (UK Biotechnology and Biological Sciences Research Council). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

 

Competing Interests: The authors have declared that no competing interests exist.

 

* E-mail: nora.hunter@roslin.ed.ac.uk

 


 

 >>>Further studies are clearly necessary in order to understand the underlying mechanisms and to be able to assess whether the very different placental structures in humans will protect babies from infection if born to CJD infected mothers.<<<

 

Evidence of in utero transmission of classical scrapie in sheep

 

John Spiropoulos⇑, Stephen A.C. Hawkins, Marion M. Simmons and Susan J. Bellworthy

 

+ Author Affiliations Animal Health and Veterinary Laboratories Agency (AHVLA) Weybridge, Addlestone, Surrey KT15 3NB, UK

 

ABSTRACT

 

Classical scrapie is one of the Transmissible Spongiform Encephalopathies (TSE), a group of fatal infectious diseases that affect the central nervous system (CNS). Classical scrapie can transmit laterally from ewe to lamb perinatally, or between adult animals. Here we report detection of infectivity in tissues of an unborn foetus, providing evidence that in utero transmission of classical scrapie is also possible.

 

FOOTNOTES Corresponding Author: John Spiropoulos: Department of Pathology, Animal Health and Veterinary Laboratories Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, Email: john.spiropoulos@ahvla.gsi.gov.uk, Tel: +44 (0) 1932 357795, Fax: +44 (0) 1932 357805 Copyright © 2014, American Society for Microbiology. All Rights Reserved.

 


 

Tuesday, September 17, 2013

 

Mother to Offspring Transmission of Transmissible Spongiform Encephalopathy TSE prion disease snip... Maternal CWD infection also appears to result in lower percentage of live birth offspring. In addition, evolving evidence from protein misfolding cyclic amplification (PMCA) assays on fetal tissues suggest that covert prion infection occurs in utero. Overall, our findings demonstrate that transmission of prions from mother to offspring can occur, and may be underestimated for all prion diseases.

 

snip...

 

Here, in an experimental model of CWD, we have demonstrated the transmission of infectious prions from clinical and subclinical mothers to full-term viable, nonviable and in utero harvested offspring, revealing that the transmission of TSEs from mother to offspring can occur and may be underestimated for all prion diseases. snip... please see full text ; Tuesday, September 17, 2013

 

*** Mother to Offspring Transmission of Transmissible Spongiform Encephalopathy TSE prion disease ***

 


 

Friday, May 10, 2013

 

Evidence of effective scrapie transmission via colostrum and milk in sheep

 


 

Tuesday, April 30, 2013

 

Transmission of classical scrapie via goat milk

 

Veterinary Record2013;172:455 doi:10.1136/vr.f2613

 


 

Envt.18: Mother to Offspring Transmission of Chronic Wasting Disease

 

Candace K. Mathiason,† Amy Nalls, Kelly Anderson, Jeanette Hayes-Klug, Jenny G. Powers, Nicholas J. Haley and Edward A. Hoover

 

Colorado State University; Fort Collins, CO USA†Presenting author; Email: ckm@lamar.colostate.edu

 

We have developed a new cervid model in small Asian muntjac deer (Muntiacus reevesi) to study potential modes of vertical transmission of chronic wasting disease (CWD) from mother to offspring. Eight of eight (8/8) muntjac doe orally infected with CWD tested PrPCWD lymphoid positive by four months post infection. Ten fawns were born to these CWD-infected doe— four of the fawns were viable, five were non-viable and one was a first trimester fetus harvested from a CWD-infected doe euthanized at end-stage disease. The viable fawns have been monitored for CWD infection by immunohistochemistry and sPMCA performed on serial tonsil and rectal lymphoid tissue biopsies. PrPCWD has been detected in one fawn by IHC as early as 40 days of age. Moreover, sPMCA performed on rectal lymphoid tissue has yielded positive results on another fawn at ten days of age. In addition, sPMCA assays have demonstrated amplifiable prions in fetal placental or spleen tissue of three non-viable fawns and mammary tissue of the dams.

 

Additional pregnancy related fluids and tissues from the doe as well as tissue from the nonviable fawns are currently being probed for the presence of CWD. In summary, we have employed the muntjac deer model, to demonstrate for the first time the transmission of CWD from mother to offspring. These studies provide the foundation to investigate the mechanisms and pathways of maternal prion transfer.

 

===========================

 

PPo3tss-18: A Possible Case of Maternal Transmission of the BSE Agent within Captive Cheetah Affected with Feline Spongiform Encephalopathy

 

Anna Bencsik, Sabine Debeer, Thierry Petit and Thierry Baron

 

Afssa; Unité ATNC; Lyon, France; Zoo de la Palmyre; Les Mathes, France

 

Key words: BSE, FSE, vertical transmission

 

Introduction. Feline spongiform encephalopathy (FSE) is considered to be related to bovine spongiform encephalopathy (BSE). It has been reported in domestic cats as well as in captive wild cats including cheetahs, first in the United Kingdom (UK) and then in other European countries. In France, several cases were described in cheetahs either imported from UK or born in France. Here we report details of two other FSE cases in captive cheetah. These cases are of particular interest since the 2nd case of FSE in a cheetah born in France, appears most likely due to maternal transmission.1

 

Results. Complete PrPd study showed the close likeness between the two cheetah cases. The TgOvPrP4 mouse brains infected with cattle BSE and cheetah FSE revealed similar vacuolar lesion profiles, PrPd brain mapping with occurrence of typical florid plaques.

 

Materials and Methods. Using immunohistochemistry (IHC), pathological form of PrP(PrPd) was analyzed in the brains and peripheral organs of these two cheetahs. Transmission studies to the TgOvPrP4 mouse line were also performed, for comparison with the transmission of cattle BSE. Lesion profiles of the infected transgenic mice were analyzed as well as type and brain distribution of PrPd.

 

Conclusion. Collectively, these data indicate that both FSE cases harbor the same strain of agent as the cattle BSE agent. Because this is most probably a case of maternal transmission of the disease, this new observation may have some impact on our knowledge of vertical transmission of BSE agent-linked TSEs such as in human variant Creutzfeldt Jakob disease.

 

References

 

1. Bencsik et al. PLoS One 2009; 4:6929.

 

=========================

 

PPo3tss-40: Mother to Offspring Transmission of Chronic Wasting Disease

 

Candace K. Mathiason, Amy V. Nalls, Kelly Anderson, Jeanette Hayes-Klug, Nicholas Haley and Edward A. Hoover

 

Colorado State University, Department of Microbiology, Immunology and Pathology, Fort Collins, CO USA

 

Key words: Chronic wasting disease, vertical transmission, muntjac deer

 

We have developed a new cervid model in small Asian muntjac deer (Muntiacus reevesi) to study potential modes of vertical transmission of chronic wasting disease (CWD) from mother to offspring. Eight of eight (8/8) muntjac doe orally infected with CWD tested PrPCWD lymphoid positive by 4 months post infection. Six fawns were born to these CWD-infected doe. Six fawns were born to 6 CWD-infected doe; 4 of the fawns were non-viable. The viable fawns have been monitored for CWD infection by immunohistochemistry and sPMCA performed on serial tonsil and rectal lymphoid tissue biopsies. PrPCWD has been detected in one fawn as early as 40 days of age. Moreover, sPMCA performed on rectal lymphoid tissue has yield positive results on another fawn at 10 days of age. In addition, sPMCA assays have also demonstrated amplifiable prions in maternal placental (caruncule) and mammary tissue of the dam.

 

Additional pregnancy related fluids and tissues from the doe as well as tissue from the nonviable fawns are currently being probed for the presence of CWD. In summary, we have employed the muntjac deer model, to demonstrate for the first time the transmission of CWD from mother to offspring. These studies provide the foundation to investigate the mechanisms and pathways of maternal prion transfer.

 

PRION 2011

 

landesbioscience.com

 

International Prion Congress: From agent to diseaseSeptember 8–11, 2010Salzburg, Austria

 


 

Friday, December 23, 2011

 

Detection of PrPres in Genetically Susceptible Fetuses from Sheep with Natural Scrapie

 


 

SHEEP WITH MASTITIS TRANSMIT INFECTIOUS PRIONS THROUGH THE MILK

 


 

Saturday, April 12, 2008

 

Evidence of scrapie transmission via milk

 


 

 [6] Date: Fri 4 Feb 2005

 

From: Terry S. Singeltary Sr. flounder@wt.net

 

Source: Spongiform Encephalopathy Advisory Committee (SEAC), Position Paper, January 2005 [edited]

 


 

Position Statement: Maternal Transmission of variant Creutzfeldt-Jakob disease Issue:

 

1. The Chief Medical Officer for England asked SEAC to consider current evidence and comment on the potential transmission of variant Creutzfeldt-Jakob disease (vCJD) from mother to child via human breast milk. In utero transmission was also considered. The committee also commented on the scientific basis of a risk reduction measure for possible transmission of vCJD via banked breast milk. Background:

 

2. No diagnostic test is currently available for the detection of abnormal PrP in milk. Research is under way to develop tests to screen for the possible presence of abnormal prion protein (PrP) in milk samples from cattle experimentally infected with BSE [A joint FSA/SEAC milk working group is monitoring and providing advice on this research carried out at the Veterinary Laboratories Agency.] These modified tests may also be applicable to human milk. However, it is not yet clear when/if a reliable test will be available.

 

3. A small number of breast milk banks in the UK supply highly vulnerable premature babies for whom no milk may be available from the mother. A model developed by the Department of Health to assess the effect of pooling breast milk from multiple donors on the possible risks of transmission of vCJD via breast milk banks was considered.

 

4. There is some, albeit limited, published epidemiological and experimental research on maternal transmission of prion diseases. There are also unpublished surveillance data of children born to vCJD cases from the National CJD Surveillance Unit and UK surveillance of neurological illness in children which might inform on potential risks of maternal transmission. Breast milk banks:

 

5. There is no evidence that vCJD infectivity has ever been transmitted through breast milk. However, a theoretical risk exists. Modelling studies clearly show that the practice of pooling breast milk increases the number of donors to which a recipient is exposed and thereby increases the potential risk of an infant receiving milk contaminated with vCJD infectivity. The theoretical risk of infection can be minimised by not pooling the milk, by the use of individual hand operated breast milk pumps for single donors, and by the use of single-use sterilised bottles for collection. In addition, available evidence suggests that infection/inflammation of the breast results in increased lymphocytes in milk and therefore increased risk of infectivity. This risk would be minimised if milk from donors showing signs of infection were not used.

 

6. The committee suggested that, if practicable, milk could be stored for an appropriate period of time to allow the health status of donors to be monitored, before it is released. However, information was not available to the committee on whether long-term storage of human milk is detrimental to its nutritional quality. Maternal transmission

 

7. There is evidence from animal studies for low-level maternal transmission of prions in cattle and sheep. This transmission may occur in utero, via milk and/or perinatally. However, the possibility that this putative maternal transmission might have been due to another mode of transmission, for example through a contaminated environment or feed, cannot be ruled out.

 

8. In contrast, in humans there is no evidence for maternal transmission in cases of familial prion disease, other than the transfer of a mutant form of the PrP gene, and there is no evidence of maternal transmission of Kuru [a chronic, progressive, uniformly fatal nervous system disorder caused by prions, associated with cannibalism among the Fore tribe and neighboring peoples in New Guinea. - CopyEd.PG]. However, compared with other human prion diseases vCJD may pose a greater risk because of the greater involvement of the lymphoreticular system in vCJD pathogenesis. Although, breast tissue (and placenta) from a single vCJD case tested negative for PrPvCJD, transfer of infectivity to breast milk may depend on the physiological status of the mammary gland. Similar tests or infectivity bioassays have not been conducted on breast tissue from lactating patients with vCJD.

 

9. A published study suggesting transmission of sCJD in colostrum (ref. 1) was considered unreliable because tissues not normally associated with high levels of infectivity (blood and placenta) showed equivalent infectivity to that of the brain in this study.

 

10. Analysis of prospective surveillance data of UK children born to mothers with, or that had subsequently developed clinical vCJD, provide no evidence for maternal transmission of vCJD. However, the number of cases is very small and the incubation period of vCJD, if transmitted from mother to child, is unknown and so the children may yet be too young to have developed symptoms.

 

11. The phenotype of BSE infection in humans expressing PrP genotypes other than M/M at codon 129 is not known. Given recently published studies in mice expressing the human PrP gene (ref. 2), which suggest that the human PrP genotype may affect disease phenotype, the committee considered it very important that undiagnosed neurological diseases be carefully monitored. In this respect, amongst others, it is recommended that the careful monitoring of neurological illnesses through the PIND surveillance of children (ref. 3) continue. Conclusions

 

12. In summary, there is currently no epidemiological evidence for maternal transmission of vCJD, including transmission via breast milk. However, there is a hypothetical risk. Although available evidence is limited and mostly indirect rather than direct, this risk, if any, appears to be low. As a risk cannot be excluded, a watching brief should be maintained.

 

References: (1) Tamai Y et al. Demonstration of the transmissible agent in tissue from a pregnant woman with CJD. New Eng J Med 1992 327, 649. (2) Wadsworth et al. Human prion protein with valine 129 prevents expression of variant CJD phenotype. Science. 2004 306, 1793-1796. (3) Devereux G et al. Variations in neurodegenerative disease across the UK: findings from the national study of Progressive Intellectual and Neurological Deterioration (PIND). Arch DisChild. 2004 89, 8-12. -- Terry S. Singeltary Sr. flounder@wt.net ******

 

P.4.31

 

Prion infectivity in milk from ARQ/ARQ sheep experimentally infected with Scrapie and MAEDI-VISNA virus

 

Ciriaco Ligios1, Maria Giovanna Cancedda1, Antonello Carta2, Cinzia Santucciu1 Caterina Maestrale1, Francesca Demontis1, Sonia Attene1, Maria Giovanna Tilocca1, Cristiana Patta1, Massimo Basagni5, Paola Melis1, James C. De- Martini3, Christina Sigurdson4 1Istituto Zooprofilattico Sperimentale della Sardegna, Italy; 2Research Unit: Genetics and Biotechnology, DIRPA, AGRIS Sardinia, Italy; 3Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA; 4Department of Pathology, School of Medicine, University of California San Diego, USA; 5Prion Diagnostica Rho, Italy

 

Background:

 

Scrapie in sheep is characterized by the deposition of misfolded and aggregated prion protein (PrPSc) in the central nervous system (CNS) and within the lymphoreticular system (LRS). PrPSc was shown to accumulate in organs beyond the CNS and the LRS when lymphofollicular or granulomatous inflammation was also present.

 

Objectives:

 

Our aim was to determine whether ectopic PrPSc accumulation in the inflamed mammary gland of sheep with scrapie results in infectious prion secretion into the milk.

 

Methods:

 

We fed approximately 1.1 - 2.1 L of milk from sheep with lymphofollicular mastitis and clinical scrapie to each of 8 ARQ/ARQ lambs derived from scrapie-free flocks. The milk donor sheep had been previously inoculated with Maedi-Visna virus (MVV) intratracheally and intravenously and scrapie brain homogenate orally. In addition, 3 ARQ/ARQ lambs were fed approximately 1.4 – 1.7 L of milk from ARQ/ARQ sheep that had been experimentally infected with only scrapie. Additional control ARQ/ARQ lambs were inoculated with scrapie brain homogenate only, or with milk from uninfected sheep.

 

Results:

 

Two lambs which had received milk from sheep with mastitis and scrapie developed clinical signs of scrapie at 677 and 745 days post-inoculation. One additional clinically healthy lamb from this group, which was sacrificed for a cause unrelated to scrapie, was found to have PrPSc in brain and tonsil. The control lambs and those which received milk from sheep affected only with scrapie are, to date, clinically healthy.

 

Discussion:

 

This is the first evidence of clinical scrapie in sheep fed milk from scrapie sick sheep. The experiment is ongoing, however these preliminary results indicate that milk and/or colostrum from ARQ/ARQ sheep with clinical scrapie and lymphofollicular mastitis could contribute to scrapie transmission.

 


 

Monday, August 03, 2009

 

Prions Are Secreted in Milk from Clinically Normal Scrapie-Exposed Sheep

 

Journal of Virology, August 2009, p. 8293-8296, Vol. 83, No. 16 0022-538X/09/$08.00+0 doi:10.1128/JVI.00051-09 Copyright © 2009, American Society for Microbiology. All Rights Reserved.

 


 


 

TAFS INTERNATIONAL FORUM FOR TRANSMISSIBLE ANIMAL DISEASES AND FOOD SAFETY a non-profit Swiss Foundation (January, 2009) TAFS1 STATEMENT ON TRANSMISSION OF SCRAPIE VIA MILK

 


 

Prions in Milk from Ewes Incubating Natural Scrapie

 


 

ProMED-mail

 

Archive Number 20050211.0467 Published

 

Date 11-FEB-2005 Subject PRO/AH/EDR> CJD (new var.) update 2005 (02)

 

snip...

 

******

 

[3] Date: Thu 20 Jan 2005 From: Terry S. Singeltary Sr.

 

Chronic Lymphocytic Inflammation Specifies the Organ Tropism of Prions

 

Chronic Lymphocytic Inflammation Specifies the Organ Tropism of Prions

 

----------------------------------------------------------------------

 

[The following is the summary of a paper by Mathias Heikenwalder and 8 others, published in Science online, 10.1126/science.1106460, Thu 20 Jan 2005 .

 

This paper describes work that illustrates that chronic inflammatory conditions may affect and expand the natural and iatrogenic transmission of prions - Mod.CP]

 

Prions typically accumulate in nervous and lymphoid tissues. Because proinflammatory cytokines and immune cells are required for lymphoid prion replication, we tested whether inflammatory conditions affect prion pathogenesis. We administered prions to mice with 5 inflammatory diseases of kidney, pancreas or liver. In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs. Inflammatory foci consistently correlated with lymphotoxin upregulation and ectopic induction of PrPC-expressing FDC-M1+ cells, whereas inflamed organs of mice lacking lymphotoxin-alpha or its receptor accumulate neither PrPSc nor infectivity upon prion inoculation. By expanding the tissue distribution of prions, chronic inflammatory conditions may act as modifiers of natural and iatrogenic prion transmission.

 

****** [4] Date: Thu 20 Jan 2005 From: Terry S. Singeltary Sr. Source: Reuters News Agency, Thu 20 Jan 2005 [edited]

 

Study Finds that Illness May Promote Spread of Mad Cow Prion

 

------------------------------------------------------------

 

The agent that transmits mad cow disease and related diseases may spread further in the body of an animal suffering from certain illnesses, scientists said on Thu 20 Jan 2005. Their finding raises the question of whether measures aimed at curbing the spread of mad cow disease, or bovine spongiform encephalopathy (BSE), are adequate, the researchers said.

 

Tests on mice showed that prions, the protein-like fragments that transmit BSE and related diseases [e.g. variant Creutzfeldt-Jakob disease in humans], can show up in organs they are not supposed to if the mouse has an inflammatory condition. Scientists have believed that BSE-causing prions are limited to the brain, spleen, spinal cord and lymph tissue, although some tests have suggested blood and muscle tissue may also harbor the prions. The latest study, published in the journal Science, suggests prions may also sometimes be found in the kidney, pancreas and liver. "We administered prions to mice with 5 inflammatory diseases of kidney, pancreas or liver," wrote the researchers, led by top prion expert Dr. Adriano Aguzzi of the University Hospital of Zurich in Switzerland.

 

Aguzzi and colleagues in Britain and the United States inoculated specially bred mice with prions and checked to see if the prions spread in their bodies when the mice had an inflammatory condition. This is because other studies had suggested that prions might be attracted to immune system inflammatory cells. "In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs," the researchers wrote.

 

BSE peaked in British cattle herds in the mid-1990s, and a few cases have been reported in other countries. Canada reported its 3rd case this month. People who eat BSE-infected beef products can develop a related human brain disease called variant Creutzfeldt-Jakob disease or vCJD. There is no treatment or cure. [As of 4 Feb 2005, so far in the UK for the year 2005 there have 8 referrals of suspected CJD; and there have been 8 deaths from sporadic CJC, one from GSS and none from familial, iatrogenic or variant CJD. - Mod.CP]. It has killed 148 Britons, and 5 [now 6] Britons are alive with the disease, according to the British Department of Health's monthly report on the disease. The World Health Organization says it has reports of 6 cases in France, one in Ireland, one in Italy, one in Canada and one in the United States [and one in Japan: see; ProMED-mail post "CJD (new var.) - Japan: death 20050204.0381" - Mod.CP]

 

Experts believed BSE first appeared when cattle were fed improperly rendered remains of sheep infected with scrapie, a related disease. In 1997, the United States and Canada imposed animal feed bans, and have mandated the removal of materials believed to carry infectious prions. These include the skull, brain, nerves attached to the brain, eyes, tonsils, spinal cord and attached nerves, plus a portion of the small intestine. The study suggests that even symptom-free animals may also have prions in their liver, kidney, and pancreas.

 

-- Terry S. Singeltary Sr.

 

****** [5] Date: Fri 21 Jan 2005 From: ProMED-mail Souce: New York Times, Fri 21 Jan 2005 [edited]

 

Study Finds Broader Reach for Mad Cow Proteins

 

----------------------------------------------

 

Mad cow disease has long been thought to occur in just the brains and nervous systems of infected animals. But scientists are reporting today that the proteins thought to cause the disease can travel to other organs as well. The research is based on experiments with mice, but if it is borne out in other species, it may suggest that no part of an infected animal is safe to eat. The disease leads to a fatal brain disease in humans [variant Creutzfeldt-Jakob disease].

 

In the mouse experiments, reported in the journal Science [see [3] above], researchers in Switzerland found that prions, proteins that are the infectious agent in mad cow disease, follow immune cells, called lymphocytes, in the body. When mice were given chronic infectious diseases of the liver, kidney and pancreas and then inoculated with prions, the prions made their way to the infected organs. Dr. Adriano Aguzzi, a neuropathologist at the University Hospital in Zurich, who led the experiments, said this meant that cows and sheep infected with prions could harbor the disease in any inflamed organ.

 

But Dr. David R. Smith, a veterinarian at the University of Nebraska, said the research did not raise alarms about American beef. For one thing, he said, livestock with obvious signs of systemic infection, like a fever, are not allowed into the food supply. And most American cattle are slaughtered while they are young and at reduced risk of infection.

 

Many countries, including the United States, require the removal of skulls, brains, eyes, spinal cords and other nervous tissues from slaughtered animals because prions are known to accumulate in those tissues. Even in countries with mad cow disease, mainly in Europe, meat is considered safe if those tissues are removed, Dr. Aguzzi said. But the disease could spread more readily if infections are not obvious or if inspections are sloppily done, he said.

 

[Byline: Sandra Blakeslee]

 

-- ProMED-mail

 

****** [6] Date: Fri 4 Feb 2005 From: Terry S. Singeltary Sr.

 

Source: Spongiform Encephalopathy Advisory Committee (SEAC), Position Paper, January 2005 [edited]

 

Position Statement: Maternal Transmission of variant Creutzfeldt-Jakob disease

 

-----------------------------------------------

 

Issue:

 

1. The Chief Medical Officer for England asked SEAC to consider current evidence and comment on the potential transmission of variant Creutzfeldt-Jakob disease (vCJD) from mother to child via human breast milk. In utero transmission was also considered. The committee also commented on the scientific basis of a risk reduction measure for possible transmission of vCJD via banked breast milk.

 

Background:

 

2. No diagnostic test is currently available for the detection of abnormal PrP in milk. Research is under way to develop tests to screen for the possible presence of abnormal prion protein (PrP) in milk samples from cattle experimentally infected with BSE [A joint FSA/SEAC milk working group is monitoring and providing advice on this research carried out at the Veterinary Laboratories Agency.] These modified tests may also be applicable to human milk. However, it is not yet clear when/if a reliable test will be available.

 

3. A small number of breast milk banks in the UK supply highly vulnerable premature babies for whom no milk may be available from the mother. A model developed by the Department of Health to assess the effect of pooling breast milk from multiple donors on the possible risks of transmission of vCJD via breast milk banks was considered.

 

4. There is some, albeit limited, published epidemiological and experimental research on maternal transmission of prion diseases. There are also unpublished surveillance data of children born to vCJD cases from the National CJD Surveillance Unit and UK surveillance of neurological illness in children which might inform on potential risks of maternal transmission.

 

Breast milk banks:

 

5. There is no evidence that vCJD infectivity has ever been transmitted through breast milk. However, a theoretical risk exists. Modelling studies clearly show that the practice of pooling breast milk increases the number of donors to which a recipient is exposed and thereby increases the potential risk of an infant receiving milk contaminated with vCJD infectivity. The theoretical risk of infection can be minimised by not pooling the milk, by the use of individual hand operated breast milk pumps for single donors, and by the use of single-use sterilised bottles for collection. In addition, available evidence suggests that infection/inflammation of the breast results in increased lymphocytes in milk and therefore increased risk of infectivity. This risk would be minimised if milk from donors showing signs of infection were not used.

 

6. The committee suggested that, if practicable, milk could be stored for an appropriate period of time to allow the health status of donors to be monitored, before it is released. However, information was not available to the committee on whether long-term storage of human milk is detrimental to its nutritional quality. Maternal transmission

 

7. There is evidence from animal studies for low-level maternal transmission of prions in cattle and sheep. This transmission may occur in utero, via milk and/or perinatally. However, the possibility that this putative maternal transmission might have been due to another mode of transmission, for example through a contaminated environment or feed, cannot be ruled out.

 

8. In contrast, in humans there is no evidence for maternal transmission in cases of familial prion disease, other than the transfer of a mutant form of the PrP gene, and there is no evidence of maternal transmission of Kuru [a chronic, progressive, uniformly fatal nervous system disorder caused by prions, associated with cannibalism among the Fore tribe and neighboring peoples in New Guinea. - CopyEd.PG]. However, compared with other human prion diseases vCJD may pose a greater risk because of the greater involvement of the lymphoreticular system in vCJD pathogenesis. Although, breast tissue (and placenta) from a single vCJD case tested negative for PrPvCJD, transfer of infectivity to breast milk may depend on the physiological status of the mammary gland. Similar tests or infectivity bioassays have not been conducted on breast tissue from lactating patients with vCJD.

 

9. A published study suggesting transmission of sCJD in colostrum (ref. 1) was considered unreliable because tissues not normally associated with high levels of infectivity (blood and placenta) showed equivalent infectivity to that of the brain in this study.

 

10. Analysis of prospective surveillance data of UK children born to mothers with, or that had subsequently developed clinical vCJD, provide no evidence for maternal transmission of vCJD. However, the number of cases is very small and the incubation period of vCJD, if transmitted from mother to child, is unknown and so the children may yet be too young to have developed symptoms.

 

11. The phenotype of BSE infection in humans expressing PrP genotypes other than M/M at codon 129 is not known. Given recently published studies in mice expressing the human PrP gene (ref. 2), which suggest that the human PrP genotype may affect disease phenotype, the committee considered it very important that undiagnosed neurological diseases be carefully monitored. In this respect, amongst others, it is recommended that the careful monitoring of neurological illnesses through the PIND surveillance of children (ref. 3) continue.

 

Conclusions

 

12. In summary, there is currently no epidemiological evidence for maternal transmission of vCJD, including transmission via breast milk. However, there is a hypothetical risk. Although available evidence is limited and mostly indirect rather than direct, this risk, if any, appears to be low. As a risk cannot be excluded, a watching brief should be maintained.

 

References:

 

(1) Tamai Y et al. Demonstration of the transmissible agent in tissue from a pregnant woman with CJD. New Eng J Med 1992 327, 649.

 

(2) Wadsworth et al. Human prion protein with valine 129 prevents expression of variant CJD phenotype. Science. 2004 306, 1793-1796.

 

(3) Devereux G et al. Variations in neurodegenerative disease across the UK: findings from the national study of Progressive Intellectual and Neurological Deterioration (PIND). Arch DisChild. 2004 89, 8-12.

 

-- Terry S. Singeltary Sr.

 

******

 

snip...

 

ProMED-mail promed@promedmail.org

 


 

 

******[6]Date: Fri 4 Feb 2005

 

From: Terry S. Singeltary Sr.

 

Source: Spongiform Encephalopathy Advisory Committee (SEAC), Position Paper, January 2005 [edited]

 


 

snip...

 

******[6]Date: Fri 4 Feb 2005

 

From: Terry S. Singeltary Sr.

 

Source: Spongiform Encephalopathy Advisory Committee (SEAC), Position Paper, January 2005 [edited]

 

 


 

 

SNIP...SEE FULL TEXT ; p.s. ProMed archives are pay-per-view now. ...tss

 


 

 

SNIP...SEE FULL TEXT ;

 


 


 

 

cjd mother to child transmission ???

 

Mother passes on CJD to unborn baby Sun, 17 Sep 2000 Telegraph By Rajeev Syal, Jenny Booth and Chris Hastings

 


 


 

 

Dr Will offers me a tour of the laboratories. As we are getting up to go, I broach something that has been bothering me. Does he think the victims will get any younger?

 

'Well, we now have a 12-year-old.'

 

A 12-year-old?

 

'That's what I said.' He looks almost ashamed.

 

Girl or boy?

 

'I can't say.'

 

But if the incubation period is at least 10 years, then the child was barely eating solid food when it contracted the infection. 'I'm not saying anything,' the neurologist says wearily. 'You've got small children of your own, Allison. You do the maths.'

 


 

The child has been ill since she was born but tests to pinpoint the cause of the problem have so far proved inconclusive INCONCLUSIVE. What does not put an end to a thing. Inconclusive presumptions are those which may be overcome by opposing proof; for example, the law presumes that he who possesses personal property is the owner of it, but evidence is allowed to contradict this presumption, and show who is . At birth the baby, who cannot be named for legal reasons, could not swallow and was unable to gain weight.

 


 

 

Wednesday, December 30, 2009

 

Is there evidence of vertical transmission of variant CJD ?

 

J Neurol Neurosurg Psychiatry doi:10.1136/jnnp.2009.172148

 

Is there evidence of vertical transmission of variant CJD?

 

Katy Murray (kmurray12@doctors.org.uk) + Author Affiliations

 

NationalCJD Surveillance Unit, United Kingdom James Peters (jimmypeters1980@yahoo.co.uk) + Author Affiliations

 

NationalCJD Surveillance Unit, United Kingdom Lesley Stellitano (lesley.stellitano@addenbrookes.nhs.uk) + Author Affiliations

 

Addenbrooke's Hospital, United Kingdom Annemarie Winstone (annemarie.winstone@addenbrookes.nhs.uk) + Author Affiliations

 

Addenbrooke's Hospital, United Kingdom Christopher Verity (christopher.verity@addenbrookes.nhs.uk) + Author Affiliations

 

Addenbrooke's Hospital, United Kingdom Robert Will (r.g.will@ed.ac.uk) + Author Affiliations

 

NationalCJD Surveillance Unit, United Kingdom Published Online First 27 April 2009 Abstract Objectives: The possibility of vertical transmission of variant CJD (vCJD) has been raised, because of the widespread distribution of infectivity in vCJD and the demonstration that this condition can be transmitted through blood transfusion. The aim is to search for evidence of this type of transmission of vCJD.

 

Methods: A national surveillance system for CJD has been established in the UK since 1990. Through this register details were extracted of all children born to vCJD cases up to March 2009. This list was checked against the CJD register and cases identified through the UK study of progressive intellectual and neurological deterioration in children (PIND) to determine whether any of the children of vCJD cases had themselves developed a progressive neurological disorder or vCJD.

 

Results: 125 children have been born to parents with a diagnosis of vCJD. Nine of these children were born to females with vCJD who were symptomatic at conception, birth or within a year of clinical onset. Only one woman was known to have breast fed her child. None of the children of vCJD cases have been referred to the NCJDSU as suspected vCJD and none have been classified as suffering from a progressive neurodegenerative disorder through the PIND study. One of the children has been investigated by the National Prion Unit (see accompanying case report).

 

Interpretation: To date there is no evidence of vertical transmission of vCJD. However, the incubation period through this mechanism might be prolonged and it will be many years before observational data can exclude this possibility.

 


 

snip...see more here ;

 

Wednesday, December 30, 2009

 

Is there evidence of vertical transmission of variant CJD ?

 


 

Medical Devices Containing Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices) [Docket No. FDA–2013–D–1574]

 


 

 

2013 Tuesday, September 17, 2013

 

*** Mother to Offspring Transmission of Transmissible Spongiform Encephalopathy TSE prion disease ***

 

To date, 125 children have been born to women who later developed CJD [11]. This is concerning because PrPCJD has been detected in the fetal and pregnancy related tissues of a woman infected with CJD [12]. Although decades may pass before the onset of clinical effects associated with such transmission due to a long subclinical carrier state, the probability that these individuals harbor infectious prions remains high.

 


 

Sunday, August 25, 2013

 

Prion2013 Chronic Wasting Disease CWD risk factors, humans, domestic cats, blood, and mother to offspring transmission

 

snip...

 

Oral.08: Mother to offspring transmission of chronic wasting disease in Reeve's Muntjac deer Amy Nalls,1 Erin McNulty,1 Jenny Powers,2 Davis Seelig,1 Clare Hoover,1 Nicholas Haley,1 Jeanette Hayes-Klug,1 Kelly Anderson,1 Paula Stewart,3 Wilfred Goldmann,3 Edward A. Hoover1 and Candace K. Mathiason1 1Colorado State University; Fort Collins, CO USA; 2National Park Service; Fort Collins, CO USA; 3The Roslin Institute and Royal School of Veterinary Studies; Edinburgh, UK To investigate the role mother to offspring transmission plays in chronic wasting disease (CWD), we have developed a cervid model employing the Reeve's muntjac deer (Muntiacus reevesi). Eight muntjac doe were orally inoculated with CWD and tested PrPCWD lymphoid positive by 4 mo post infection. Fourteen fawns were born to these eight CWD-infected doe-3 were born viable, 6 were born non-viable and 5 were harvested as fetuses from early or end-stage CWD-infected doe. All three viable fawns have demonstrated CWD IHC lymphoid biopsy positivity between 43 d post birth and 11 mo post birth. Two of these three CWD positive viable offspring have developed clinical signs consistent with TSE disease (28-33 mo post birth). Moreover, CWD prions have been detected by sPMCA in 11 of 16 tissues harvested from 6 full-term non-viable fawns and in 7 of 11 fetal tissues harvested in utero from the second and third trimester fetuses. Additional tissues and pregnancy related fluids from doe and offspring are being analyzed for CWD prions. In summary, using the muntjac deer model we have demonstrated CWD clinical disease in offspring born to CWD-infected doe, and in utero transmission of CWD from mother to offspring. These studies provide basis to further investigate the mechanisms of maternal transfer of prions.

 

snip...

 

Sunday, August 25, 2013

 

Prion2013 Chronic Wasting Disease CWD risk factors, humans, domestic cats, blood, and mother to offspring transmission

 

 


 

 

>>> Here, in an experimental model of CWD, we have demonstrated the transmission of infectious prions from clinical and subclinical mothers to full-term viable, nonviable and in utero harvested offspring, revealing that the transmission of TSEs from mother to offspring can occur and may be underestimated for all prion diseases. <<<

 

 

2014

 

 

Sunday, January 19, 2014

 

National Prion Disease Pathology Surveillance Center Cases Examined1 as of January 8, 2014

 


 

 

Thursday, January 23, 2014

 

Medical Devices Containing Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices) [Docket No. FDA–2013–D–1574]

 


 

 

Monday, January 27, 2014

 

Evidence of in utero transmission of classical scrapie in sheep

 


 

 

 

Terry S. Singeltary Sr.

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