Sporadic Creutzfeldt-Jakob Disease among Physicians, Germany, 1993–2018 high proportion of physicians with sCJD were surgeons
Volume 26, Number 8—August 2020
CME ACTIVITY - Research
Sporadic Creutzfeldt-Jakob Disease among Physicians, Germany, 1993–2018
Peter Hermann1Comments to Author , Johannes Treig1, Steffen Unkel, Stefan Goebel, Timothy Bunck, Martha Jünemann, Tim Friede, and Inga Zerr Author affiliations: University Medical Center Göttingen, Göttingen, Germany (P. Hermann, J. Treig, S. Unkel, S. Goebel, T. Bunck, M. Jünemann, T. Friede, I. Zerr); German Center for Neurodegenerative Diseases, Göttingen (I. Zerr)
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Abstract
We investigated sporadic Creutzfeldt-Jakob disease (sCJD) among physicians in Germany by analyzing occupational information of patients with sCJD recorded by the German CJD Surveillance Unit (1993–2005; 1,250 patients, of whom 4 [0.32%] were physicians) and the National Reference Center for Human Spongiform Encephalopathies (2006–2016; 1,491 patients, of whom 13 [0.87%] were physicians). Among the physicians, we did not identify any neurologists, neurosurgeons, psychiatrists, or pathologists. A cumulative sum test showed an increase in reported physicians over time. Data for 2017–2018 indicated an increased rate of physicians among all notified sCJD cases (5/239 [2.1%]) when we used the total population of Germany as control group. Our data suggest the possibility of an increased risk for sCJD among physicians in Germany. However, we can only speculate about the reasons, and larger multinational studies are needed to replicate the finding and to clarify whether this finding is a general or a country-specific phenomenon.
Creutzfeldt-Jakob disease (CJD) is a syndrome comprising dementia and various neurologic signs and symptoms (1) caused by the transmissible misfolded prion protein scrapie (2). Reported death rates and incidence rates differ from 1.67 (3) to >2 per million person-years (4,5). In contrast to animal prion diseases (6,7), transmitted human prion diseases are uncommon. Variant CJD (vCJD) caused by ingestion of beef is rare (231 cases worldwide) (8), and its incidence has decreased since 2000 (9). Most cases of human prion disease are sporadic CJD (sCJD; 84%–93%), followed by genetic CJD (5%–10%). Only <4 a="" ambiguous="" among="" an="" and="" are="" be="" because="" been="" blood="" but="" by="" cadaver-derived="" can="" case="" cases="" caused="" characteristics="" classic="" clinical="" confirmed="" considered="" contamination="" corneal="" criteria="" data="" diagnostic="" donors="" dura="" factor="" for="" from="" grafts="" growth="" hand="" has="" history="" hormones="" however="" iatrogenic="" icjd="" identify="" imply="" in="" increased="" instrument="" is="" issue="" known="" likely="" mater="" might="" neuropathologic="" neurosurgical="" no="" of="" on="" only="" other="" overlooked="" persons="" presence="" present.="" products="" recipients="" recorded="" related="" remain="" reported="" risk="" scjd="" span="" subgroup="" surgery="" the="" this="" to="" transfusion="" transmitted="" unrecorded="" vcjd="" was="" were="" when="" with="">
An increased risk for iCJD among caregivers and healthcare professionals has been suggested, but its evaluation is complex (21–24). Previous studies neither unequivocally displayed nor ruled out relevant increases in risk for CJD among healthcare professionals (25,26). Furthermore, these investigations were mostly designed as case–control studies, which are prone to bias because of case selection. Therefore, we aimed to evaluate sCJD among physicians using historical epidemiologic data from 25 years of CJD surveillance in Germany and the whole population of that country as controls.
Methods Study Design and Data Acquisition In the framework of a retrospective cohort study, we evaluated 4,645 patient files representing all suspected CJD cases reported to the German surveillance group during June 1993–December 2016 about the patient’s occupational history to identify physicians of all specialties. In addition and as negative controls, we collected information about other professions.
The centralized assessment of suspected human prion diseases in Germany started in June 1993 and was conducted by the CJD Surveillance Unit of the University Medical Center Goettingen. Since January 2006, health authorities have officially charged this center with CJD surveillance and named it the National Reference Center for Human Transmissible Spongiform Encephalopathies (NRZ-TSE). In Germany, notification of sCJD is required. Health authorities advise clinical institutions to contact the NRZ-TSE for clinical classifications of notified cases. The NRZ-TSE counsels physicians with respect to differential diagnosis and hygienic issues and records clinical data, including the patient’s professional background. Specifically, until 2006, physicians from the CJD Surveillance Unit visited and interviewed patients and caregivers using a standardized questionnaire.
Patient Cohorts We considered all patients in the database for this study. Inclusion criteria for further analyses were diagnosis of probable or definite sCJD according to World Health Organization criteria (2) and age >35 years. We reviewed all available questionnaires (evaluated by the NRZ-TSE) and medical reports (sent to the NRZ-TSE by treating institution) since 1993 for patient’s professions to identify physicians. During 1993–2005, the research group of the University Medical Center Goettingen had to actively search for suspected CJD cases (e.g., through regular newsletters to all neurologic and psychiatric centers in Germany). Most reported patients had been visited by physicians from the research group, and epidemiologic questionnaires were available for analyses. In 2006, the group was assigned as National Reference Center, leading to a substantial increase in reported cases and resulted in a decrease in the proportion of visitations and interviews. Because of these structural differences, we divided the study cohort into cohort A (reported 1993–2005; 1,250 persons) and cohort B (reported 2006–2016; 1,491 persons) and analyzed them separately.
Population-Based Cohorts We used publicly available data on the population of Germany to create control groups in each time frame (matching cohorts A and B). Numbers of working and retired physicians were sourced from the database of the German Federal Medical Association (Bundesärztekammer [BÄK], Berlin, Germany), which provides the number of physicians and information about age, sex, specialty, and location. Membership is required for, but is not restricted to, all working physicians and does not expire with retirement. To analyze the entire population, we obtained numbers from the German Federal Office of Statistics.
Data Analyses and Statistical Methods BÄK data give numbers of physicians in Germany in different age categories. The youngest category was <35 10="" age="" and="" cohort="" controls="" differentiation="" further="" in="" included="" none="" of="" only="" patients="" physicians.="" scjd="" the="" we="" were="" without="" years="">35 years of age to achieve approximate age matching between the German physicians and the sCJD cohort. We did not further stratify for age (and sex) because of the low case count among physicians with sCJD. We pooled all data from our sources using Excel 2016 (Microsoft, https://www.microsoft.comExternal Link). We used Statistica (https://www.statsoft.deExternal Link) for descriptive analyses and performed further statistical analyses using the statistical software R version 3.4.2 (https://www.r-project.orgExternal Link). We considered results with p<0 .05="" be="" significant.="" span="" to="">
The aims of the study were to evaluate the rate of physicians in the cohort of CJD patients and to investigate a potential risk modification using population-based data. The aims had been framed before data collection. We used Fisher exact test to compare the number of physicians in the cohort of CJD patients and the number of physicians in the population of Germany.
Analyses were performed as follows. To define the number of nonphysicians in the CJD cohort, we considered only patients with known occupation. These analyses were based on the assumption of a corresponding number of physicians in the group of patients with unknown occupation. We further considered all CJD patients assuming that no additional physicians were in the group of patients with unknown occupation. We used the results to perform sensitivity analyses to evaluate the number of physicians in the group of patients with unknown occupation that would be necessary to reach statistical significance using Fisher exact test. We conducted a CUSUM (cumulative sum)–based test for a change point in a time series (27) to investigate alterations of the number of reported physicians with CJD over time (per year). Finally, in an additional step, we collected data from 2017 and 2018 and analyzed them to validate results of the previous analyses on the basis of the historical cohorts (1993–2016).
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Results Descriptive Data Analyses: CJD Cohort
Of 4,645 suspected CJD cases during June 1993–December 2016, we classified 2,754 as probable sCJD (1,543) or definite sCJD (1,211). We classified other cases as possible sCJD (2) (156 cases), non-CJD (1,188), genetic prion disease (197), and iCJD (12). A total of 338 reported cases remained unclassified because of incomplete clinical information. We reduced the number of probable and definite sCJD cases to 2,741 after excluding patients <35 17="" 1="" 2="" age.="" determined="" for="" igures="" occupation="" of="" patients="" physicians="" span="" we="" were="" whom="" years="">
In cohort A (June 1993–December 2005), we classified 539 (43%) of the 1,250 cases as probable sCJD and 711 (57%) as definite sCJD. In cohort B (January 2006–December 2016), we classified 1,000 (67%) of the 1,491 cases as probable sCJD and 491 (33%) as definite sCJD. The mean age of cohort A patients was 66 years (range 35–90 years) and of cohort B patients was 68 years (range 37–93 years). In cohort A, 58% of patients were women; in cohort B, 52%. Information about codon 129 polymorphism was available for 1,039 (83%) cohort A cases and 581 (39%) for cohort B cases (Table 1). For 1,532 (56% in cohorts A and B combined) patients, we were able to evaluate history of occupation before illness (cohort A, 1,093 patients; cohort B, 439). For some patients, >2 different professions were recorded (up to 7). We considered occupation as a physician at any point in time. Occupation as a physician was known for 4 cohort A patients (0.3% of all patients; 0.4% of cohort A patients) and 13 cohort B patients (0.9% of all patients; 3% of cohort B patients).
Physicians with sCJD (including patients from the validation cohort 2017–2018) had a broad spectrum of medical specialties. Surgical specialties were present for 14 patients (surgery without information about further specialty, 3 patients; trauma/orthopedic surgery, 5; gynecology and otolangyrology, 2 each; urology and visceral surgery, 1 each). The others had nonsurgical specialties (internal medicine, 5; anesthesiology, podiatry, and general practice, 1 each). Of all physicians with sCJD (1993–2018), 64% had a surgical specialty (Table 2); in 2018, only 31% of all physicians in German had a surgical specialty (28). Very long duration of disease occurred only among physicians with surgical specialties (mean 205 days vs. 109 days for nonsurgical specialties; overall 175 days [range 49–809 days]). We identified no hospital in Germany that had employed >1 physician with sCJD, but a complete occupational history was not available for all patients, especially in cohort B. We found no link between a physician and another known sCJD patient, but only limited information was available (Appendix Table). Most patients were not able to give detailed information about this issue because of progressed cognitive impairment. The rate of autopsy-confirmed cases was 55%. Prion typing was performed in only 4 cases.
Descriptive Data Analyses: Population-Based Cohort The number of physicians in Germany increased from 297,803 in 1993 to 496,240 in 2016 (29), a factor of 1.67. For each period corresponding to cohort A (1993–2005) and cohort B (2006–2016), mean values of yearly numbers were calculated that excluded physicians <35 1993="" 2006="" 240="" 295="" 349="" 382="" 44="" 47="" 51="" age.="" age="" and="" calculations="" considering="" during="" entire="" germany="" in="" mean="" numbers="" of="" performed="" population="" range="" same="" span="" the="" we="" were="" years="">
Rate of Physicians in sCJD Cohorts and in the Total Population of Germany We based contingency tables on the numbers of all patients in the study cohort for whom occupation was known (cohort A, 1,093 patients; cohort B, 439 patients), all physicians in the sCJD cohort (cohort A, 4 patients; cohort B, 13 patients), the population of Germany, and all physicians in that population (Table 3). Fisher exact test yielded an odds ratio (OR) of 0.59 (95% CI 0.16–1.52; p = 0.44) for cohort A and OR 4.09 (95% CI 2.16–7.06; p<0 .001="" 3="" a="" able="" b="" cohort="" for="" germany.="" higher="" in="" indicate="" of="" physicians="" population="" rate="" results="" significantly="" span="" than="" the="" these="" total="">
We based this approach on the assumption of a corresponding proportion of physicians and nonphysicians in the group of sCJD patients without known occupational history. In a second step, we included the entire study cohort, assuming there were no additional physicians in the group of sCJD patients for whom occupational history was not known. Cohort A did not differ significantly from the total population of Germany (OR 0.52 [95% CI 0.14–1.33]; p = 0.27); likewise, cohort B did not differ significantly from the total population of Germany (OR 1.18 [95% CI 0.63–2.02]; p = 0.54). Subsequently, we conducted a sensitivity analysis to determine the number of physicians in the group without known occupation who would be required for a statistically significant difference between the study cohort and the total German population: 9 for cohort A (p = 0.03) and 5 for cohort B (p = 0.047). In a forth step, we investigated the change of the rate of reported physicians in the study cohort over time: 0.32% for cohort A (1993–2005) and 0.87% for cohort B. Results of our CUSUM test showed an increase of reported cases (p = 0.04) and identified a change point from 2008 to 2009.
Postanalytic Evaluation of 2017 and 2018 In 2017 and 2018, a total of 239 sCJD patients were reported (129 in 2017, 110 in 2018). We identified 5 physicians (1 in 2017, 4 in 2018) (Figure 2). Including the entire postanalytic cohort (sCJD patients 2017–2018), regardless of known occupational history and using population data from 2017 (29,30), excluding patients <35 1.08="" 2.61="" 3="" a="" able="" age="" among="" by="" ci="" elevated="" exact="" fisher="" found="" of="" p="0.05" patients="" physicians="" rate="" scjd="" significantly="" span="" test="" we="" years="">
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Discussion Although prion diseases are transmissible, homozygosity for methionine at codon 129 (an intrinsic factor) is the only established risk factor for sCJD (11,31). Case–control studies have shown slightly elevated ORs for several features; for example, work at an animal laboratory, ophthalmologic surgery (32), ingestion of raw meat and brain (24), and history of brain surgery (33) (Table 4). Being employed as health professionals was a risk in a meta-analysis of case–control studies (34) but was not confirmed in a later prospective study (23). Because of the methodologic approaches used, most results were nonsignificant or prone to biases (17,43). Only 1 study used large population-based data from a US death registry (6 million cases screened, 636 CJD cases and 3,180 controls selected) and identified working as a butcher and work in physicians’ offices as occupational risk factors (35). Other investigations of occupational risk factors for sCJD are not available, but the presence of unpublished data that might show inconclusive or null results cannot be excluded. Data on the development of reported cases over time with respect to occupational history are not available.
In addition to selection bias, the lack of studies that could validate occupational risk factors for sCJD might be caused by multiple comparisons of too many variables causing insignificant results. For this study, we focused on the evaluation of employment as physician as potential risk factor for sCJD. We used data from a prospective epidemiologic surveillance database in Germany and population-based data as controls.
Our first analysis showed a significantly elevated rate of physicians in the study cohort (OR 4.09; p<0 .001="" 2006="" a="" an="" as="" available="" b.="" b="" be="" because="" been="" bias.="" by="" case="" classification="" clinical="" cohort="" conducted.="" control="" data="" design="" during="" epidemiologic="" examined.="" examined="" exclusion="" for="" from="" had="" hand="" history="" hospitals="" in="" likely="" limited="" many="" may="" more="" most="" notifying="" occupation="" occupational="" of="" on="" only="" other="" others="" patients="" person="" physician="" possibility="" precise="" proportion="" relevant="" reported="" represents="" scjd="" selection="" span="" structured="" study="" surveillance="" suspected="" than="" the="" to="" unknown="" was="" were="" whereas="" which="" with="" years="">
Nonetheless, our second analysis of the entire CJD population and found no significant results (OR 0.53 [p = 0.27] for cohort A; OR 1.18 [p = 0.543] for cohort B). Therefore, we performed a sensitivity analysis indicating 5 additional physicians in the group with unknown occupational history (1,052 [71%]) in cohort B who would be necessary for a significant result. This number was higher in cohort A (9 patients), although the number of patients in cohort A with unknown occupation was much smaller (157 [13%]). These findings suggest that the number of reported physicians with sCJD increased in later years, whereas the reported number of sCJD cases was stable. We validated this finding with a CUSUM test (p = 0.04, change point from 2008 to 2009). During 2017–2018, the increased rate of sCJD in physicians was significant, even when we included all 239 reported cases in the analysis (OR 2.61; p = 0.05).
Fourteen of the 22 physicians were surgeons, but none had worked in neurosurgery and only 1 had worked in a neuropathology department for 1 year. This finding is remarkable because the high proportion of surgeons (64%) versus nonsurgeons (36%) in the sCJD group differs from the population control (39% vs. 61%). The apparent differences of clinical characteristics (age of onset, disease duration) might be explained by slightly different distribution of codon 129 genotypes in the 2 groups. Because of the low number of cases, we could not investigate these observations further. In most cases, information about genotype, prion type, and neuropathologic characteristics was insufficient to identify or exclude iCJD. No neurologists or psychiatrists were reported. We could not find regional links within the group of physicians or with other sCJD patients who had received surgical interventions and might have been index patients for obscure iCJD. Thus, we were not able to establish a causal relation between the statistical risk factor (occupation as a physician) and the disease. Nonetheless, this finding must be interpreted with regard to potential incubation times of up to 30 years (10) and incomplete information about residence history in most patients from cohort B.
Although the use of a very large cohort of patients with sCJD and a population-based control group is a strength of our investigation, the study has several limitations. Because of the low number of physicians with sCJD, every bias in the case group would cause an immense effect on statistical analyses (e.g., unrecorded cases, misdiagnosed cases). Thus, we must interpret our results cautiously. Definite (neuropathologic) diagnosis was available only for some cases in our study, but the high accuracy of clinical diagnoses performed by our center has been reported previously (5). The altered status of the surveillance group after it was named a National Reference Center in 2006 might be a source of bias. We cannot exclude that the surveillance system in Germany has improved over the years, but the available data of patients’ occupations has decreased in recent years (Table 1), which makes an underestimation of the number of physicians before 2006 highly unlikely. An increased awareness for CJD among German physicians resulting in more reported cases in recent years is also unlikely regarding the decreasing worldwide incidence of vCJD since 2000.
Another limitation of our study is the lack of further and more detailed statistical analyses. We could not calculate individual ORs for certain medical specialties. Only an extremely large-scale study pooling data from multiple national reference centers would be capable of doing that. In addition, we were not able to stratify ORs by age and sex. The age cutoff of >35 years was an attempt only to achieve an approximate matching of age in the case and the control groups. On the other hand, recorded physicians with sCJD showed a strong tendency to be male and have an age at onset of 60–75 years. In this context, unstratified analyses might underestimate ORs. Another limitation of the study is that we analyzed only 1 occupational risk factor. Other professionals, such as laboratory scientists or nurses, should be carefully considered, but the lack of data (especially population-based figures) prevented from further analyses.
The high proportion of physicians among patients with sCJD and its increase over the last years were displayed in a statistical model based on data from the population of Germany. We showed that sCJD patients were significantly more likely than the general population to be physicians, suggesting that it might be an occupational risk factor. Previous epidemiologic studies have not clearly identified an elevated risk for sCJD among physicians (Table 4), but the most recent available data are from 2010. Our study yielded significant results only after 2005, and the CUSUM test identified an increased number of physicians with sCJD after 2008. No specialties involved specifically in treating patients with CJD have been reported. Nonetheless, we found that a high proportion of physicians with sCJD were surgeons, although we can only speculate about the reasons. A larger study comprising new data from other countries is needed to clarify whether this finding is a general or a country-specific phenomenon.
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Dr. Hermann is is a study physician in the NRZ-TSE at the University Medical Center Göttingen. His research interests are diagnostic testing and epidemiology of prion diseases as well as biomarkers of atypical dementia.
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Acknowledgments We thank physicians throughout Germany for case notification and provision of clinical data to the NRZ-TSE and CJD Surveillance Unit.
This study was funded by the Robert Koch Institute through funds from the Federal Ministry of Health (grant no. 1369–341).
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References
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Friendly fire, pass it forward, they call it iatrogenic cjd, or what i call 'tse prion poker', are you all in $$$
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd, PLUS, SPORADIC CJD HAS NOW BEEN LINKED TO ATYPICAL AND TYPICAL BSE, SCRAPIE, AND NOW CWD. ...terry
SUNDAY, JULY 19, 2020
Joseph J. Zubak Orthopaedic surgeon passed away Monday, July 6, 2020, Creutzfeldt-Jakob Disease (CJD)
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.
TO THE EDITOR:
We report a case of variant Creutzfeldt–Jakob disease (CJD) that was plausibly related to accidental occupational exposure in a technician who had handled murine samples contaminated with the agent that causes bovine spongiform encephalopathy (BSE) 7.5 years earlier.
In May 2010, when the patient was 24 years of age, she worked in a prion research laboratory, where she handled frozen sections of brain of transgenic mice that overexpressed the human prion protein with methionine at codon 129. The mice had been infected with a sheep-adapted form of BSE. During this process, she stabbed her thumb through a double pair of latex gloves with the sharp ends of a curved forceps used to handle the samples. Bleeding was noted at the puncture site.
In November 2017, she began having burning pain in the right shoulder and neck. The pain worsened and spread to the right half of her body during the following 6 months. In November 2018, an examination of a sample of cerebrospinal fluid (CSF) obtained from the patient was normal. Magnetic resonance imaging (MRI) of the brain showed a slight increase in the fluid-attenuated inversion recovery (FLAIR) signal in the caudates and thalami (Fig. S1A and S1B in the Supplementary Appendix, available with the full text of this letter at NEJM.org). In January 2019, she became depressed and anxious and had memory impairment and visual hallucinations. There was hypertonia on the right side of her body. At that time, an analysis of CSF for 14-3-3 protein was negative. In March 2019, MRI showed an increased FLAIR signal in pulvinar and dorsomedial nuclei of thalami (Fig. S1C through S1E).
The patient was found to be homozygous for methionine at codon 129 of the prion protein gene without mutation. An analysis of a sample of CSF on real-time quaking-induced conversion analysis was negative for a diagnosis of sporadic CJD. However, an analysis of plasma and CSF by means of protein misfolding cyclic amplification was positive for the diagnosis of variant CJD (Figure 1A and 1B). The patient died 19 months after the onset of symptoms. Neuropathological examination confirmed the diagnosis of variant CJD (Figure 1C and 1D). Western blot analysis showed the presence of type 2B protease-resistant prion protein in all sampled brain areas. The clinical characteristics of the patient and the postmortem neuropathological features were similar to those observed in 27 patients with variant CJD who had previously been reported in France.1 (Additional details are provided in the Supplementary Appendix.)
There are two potential explanations for this patient’s condition. Oral transmission from contaminated cattle products cannot be ruled out because the patient was born at the beginning of the French BSE outbreak in cattle. However, the last two patients who had confirmed variant CJD with methionine homozygosity at codon 129 in France and the United Kingdom died in 2014 and 2013, respectively, which makes oral transmission unlikely. In France, the risk of variant CJD in 2019 was negligible or nonexistent in the post-1969 birth cohort.2
Percutaneous exposure to prion-contaminated material is plausible in this patient, since the prion strain that she had handled was consistent with the development of variant CJD.3 The 7.5-year delay between the laboratory accident and her clinical symptoms is congruent with the incubation period in the transfusion-transmitted form of the disease. The ability of this strain to propagate through the peripheral route has been documented, and experimental studies with scrapie strains have shown that scarification and subcutaneous inoculation are effective routes.4,5 The last known Italian patient with variant CJD, who died in 2016, had had occupational contact with BSE-infected brain tissues, although subsequent investigation did not disclose a laboratory accident (Pocchiari M, Italian Registry of CJD: personal communication). Thus, the last two cases of variant CJD outside the United Kingdom have been associated with potential occupational exposure. Such cases highlight the need for improvements in the prevention of transmission of variant CJD and other prions that can affect humans in the laboratory and neurosurgery settings, as outlined in the Supplementary Appendix.
Jean-Philippe Brandel, M.D. Assistance Publique–Hôpitaux de Paris, Paris, France
M. Bustuchina Vlaicu, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France
Audrey Culeux, B.Sc. INSERM Unité 1127, Paris, France
Maxime Belondrade, M.Sc. Daisy Bougard, Ph.D. Etablissement Français du Sang, Montpellier, France
Katarina Grznarova, Ph.D. Angeline Denouel, M.Sc. INSERM Unité 1127, Paris, France
Isabelle Plu, M.D. Elodie Bouaziz-Amar, Pharm.D., Ph.D. Danielle Seilhean, M.D., Ph.D. Assistance Publique–Hôpitaux de Paris, Paris, France
Michèle Levasseur, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France
Stéphane Haïk, M.D., Ph.D. INSERM Unité 1127, Paris, France stephane.haik@upmc.fr
Supported by a grant (ANR-10-IAIHU-06) from Programme d’Investissements d’Avenir and Santé Publique France.
Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org.
July 2, 2020 N Engl J Med 2020; 383:83-85 DOI: 10.1056/NEJMc2000687
Supplementary Appendix
This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Brandel J-P, Vlaicu MB, Culeux A, et al. Variant Creutzfeldt–Jakob disease diagnosed 7.5 years after occupational exposure. N Engl J Med 2020;383:83-5. DOI: 10.1056/NEJMc2000687
Full case report
A woman, born in 1986, with only a medical history of dental avulsion and the removal of a nevus started to complain, in November 2017, of burning pain in the right shoulder and the right side of the neck. Over the next 6 months, the pain worsened and spread to the right half-body including the buttocks, the back of the thigh and the foot sole, and the face with ear pain. After several consultations, a first hospital assessment was carried out in November 2018. CSF examination was normal and brain MRI interpreted as normal despite slight high signals in the caudate nucleus and thalami (Supplementary figure 1). The diagnosis of Lyme disease was suspected and treatment with ceftriaxone was initiated. Pain persisted and the patient who was showing signs of depression was referred to a psychiatrist for antidepressant treatment. Memory impairment was noted by relatives in January 2019 and the patient was admitted to a neurology department in February 2019. Right extrapyramidal hypertonia, visual hallucinations and memory problems of recent events were observed. Neurological alterations were associated with severe anxiety. Inflammatory markers, biological and immunological assessments were normal. Serology for conventional agents was negative. Detection of anti-neuronal, anti-thyroid peroxidase, anti-thyroglobulin and anti-thyroidstimulating hormone receptor antibodies yielded negative results. Vitamin B1 and B6 levels were within normal limits. Standard CSF analysis was normal and 14-3-3 protein detection was negative. MRI from mid-March 2019 showed a high signal on the FLAIR sequences in the pulvinar and dorsomedian nuclei of the thalamus, bilaterally, more intense than those observed in the striatum (Supplementary figure 1). A generally slow activity was observed on EEGs. PRNP analysis revealed a homozygous methionine-methionine (MM) genotype at codon 129 without mutation. At this time, the patient fulfilled criteria of probable vCJD. Two different protein misfolding amplification methods were performed. As predicted in a suspected case of vCJD, RT-QuIC detection in the CSF gave a negative result.1 A PMCA test, recently validated for the diagnosis of vCJD in plasma and CSF was performed.2,3 PMCA detection was positive in plasma and CSF. Evolution was marked by the
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worsening of cognitive impairment, a small step with balance disorders and an extrapyramidal syndrome.
The patient died 19 months after disease onset.
Neuropathological examination confirmed the diagnosis of vCJD by showing typical florid plaques in the cerebral cortex and cerebellum. Spongiform changes, gliosis and neuronal loss were predominantly observed in the subcortical gray matter. In addition, PrP immunohistochemistry showed multicentric plaques, clumpses, peri-cellular and peri-vascular PrP deposition (Supplementary figure 2). Western blot detection of PrPres was positive and type 2B PrPres was consistently detected in all studied brain areas.
The epidemiological survey revealed that the patient had been employed from 2009 to 2012 in a laboratory involved in prion research. In particular, she has worked on transgenic animal models expressing human and bovine PrP and infected with strains of human or bovine prions. The patient had two work accidents. In May 2010, she stabbed her thumb with sharp ends curved forceps used to handle brain frozen sections of humanized transgenic mice infected with a sheep-adapted BSE agent. The mouse brain handled at the time of the accident was from a secondary intra-cerebral subpassage of sheep BSE in transgenic mice overexpressing a methionine 129-human PrP. To note transmission studies indicate a low or absent transmission barrier to sheep BSE in human M129-PrP mice. The neuropathological phenotype is similar to that observed in mice infected with cattle BSE or vCJD suggesting that sheep-BSE could act as a causal vCJD agent especially in codon 129-methionine homozygotes.
4,5 The patient immediately noticed a bleeding wound. After leaving the level 3 biosafety laboratory, the wounded finger was cleaned with water and immersed for more than ten minutes in a freshly diluted 2% sodium hypochlorite solution. The second accident occurred in September 2011 in a conventional laboratory with no contact with infectious prion material. No other risk factors were identified with the exception, as most French people in her age cohort, a dietary exposure from 1986 to 1996 to bovine products with a BSE risk.
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Methods
Clinical and epidemiological data As with all other cases of French vCJD, a direct interview with the patient’s family was conducted. Clinical data were extracted from the medical records and further information was collected using the European network (EuroCJD) questionnaire. The data collected were gender, age at onset and death, clinical features, results of investigations, and specific medical risk factors. These included history of growth hormone therapy, transplantation, surgery, blood transfusion, blood products therapy (albumin, immunoglobulin, clotting factors), vaccinations, professional activity, and stays in UK. The reports of the two accidents at work were collected. Additional data were obtained from the authorities of the research institute. They explained precisely how the patient had been injured, the biological materials handled and how the wounds had been disinfected and treated. Genetic analysis The prion protein gene (PRNP) was analyzed as described previously to obtain the genotype at codon 129 and to exclude a pathogenic mutation.6 An informed consent for genetic analysis was obtained from the patient's husband.
Neuropathological analysis
Samples were taken from 1cm-thick coronal sections after two months of fixation in 10% formalin as described previously.7 After formic acid treatment, specimens were embedded in paraffin. Threemicrometer-thick sections were stained with hematoxylin and eosin and Periodic Acid–Schiff (PAS) methods. PrP immunohistochemistry was performed using the 12F10 mouse monoclonal antibody.8,9 Biochemical analysis PrPres analysis by Western blot was performed from frozen samples of the brain. Tissue homogenization, digestion with proteinase K, purification, electrophoresis and immunoblotting were
5
done as described previously.10 The biochemical classification according to Parchi and colleagues was used.11
Amplification methods
RT-QuIC analysis in the CSF was performed using hamster full-length (23–231) recombinant PrP as previously described.12 Thirty µl of CSF per well were added and analysis was performed in quadruplicate using a BMG-LABTECH Omega. PMCA amplification in plasma and CSF was performed as described by using brains from transgenic mice overexpressing human M129-PrP as substrate.2,3 For plasma samples, a capture of abnormal PrP using plasminogen-coated magnetic nanobeads was performed before serial amplification. Each round of PMCA comprised 80 cycles of 30 min incubation/20 s sonication. Implications If one considers our patient as a case of a documented accidental transmission of CJD in a research laboratory, several important points should be stressed:
- A single puncture without hollow needle containing infectious material is sufficient to transmit prions in human even with a short contact.
- The incubation period is similar to that seen in MM patients with transfusion-transmitted vCJD, suggesting that the level of accidentally delivered infectious dose is in the same range as that contained in a unit of non-leukodepleted red blood cells.
- Immersing this type of lesion in a freshly diluted 2% sodium hypochlorite solution was not sufficient to prevent contamination. Important consequences in terms of prevention of occupational risks and public health issue associated with prions should be underlined:
6
- Individual protection against accidental wounds should be reinforced in research laboratories, neuropathology department and autopsy rooms. Neurosurgery teams should take the risk into account, especially when a cortical biopsy is performed to explore patients with unexplained encephalopathy. This implies accurate information and training of exposed professionals.
- The efficacy of decontamination procedures to be applied in case of accidental exposure has not been demonstrated using adequate in vivo models of transmission. A more aggressive postexposure management is to be defined and validated experimentally.
- The mechanisms of prion neuro-invasion in this specific scenario are unknown and may involve prion propagation through (1) the peripheral innervation of digital pulp, (2) an up-take by phagocytes driving prion replication in the lymphoid system followed by propagation via the autonomous nervous system or (3) blood transport.
- No preventive treatment is available to date. While a few approaches that may limit peripheral prion propagation and neuro-invasion have been proposed (such as corticoids and pentosan polysulfate), their efficiency in such a transmission pattern and in the use of relevant prion strains has to be confirmed.
7
References
1. Zanusso G, Monaco S, Pocchiari M, Caughey B. Advanced tests for early and accurate diagnosis of Creutzfeldt-Jakob disease. Nat Rev Neurol 2016;12:325-33.
2. Bougard D, Brandel JP, Belondrade M, et al. Detection of prions in the plasma of presymptomatic and symptomatic patients with variant Creutzfeldt-Jakob disease. Science translational medicine 2016;8:370ra182.
3. Bougard D, Belondrade M, Mayran C, et al. Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification. Emerging infectious diseases 2018;24:1364-6.
4. Plinston C, Hart P, Chong A, et al. Increased susceptibility of human-PrP transgenic mice to bovine spongiform encephalopathy infection following passage in sheep. Journal of virology 2011;85:1174-81.
5. Joiner S, Asante EA, Linehan JM, et al. Experimental sheep BSE prions generate the vCJD phenotype when serially passaged in transgenic mice expressing human prion protein. J Neurol Sci 2018;386:4-11.
6. Laplanche JL, Delasnerie-Lauprêtre N, Brandel JP, et al. Molecular genetics of prion diseases in France. Neurology 1994;44:2347-51.
7. Hauw JJ, Sazdovitch V, Laplanche JL, et al. Neuropathologic variants of sporadic CreutzfeldtJakob disease and codon 129 of PrP gene. Neurology 2000;54:1641-6.
8. Haik S, Faucheux BA, Sazdovitch V, et al. The sympathetic nervous system is involved in variant Creutzfeldt-Jakob disease. Nature medicine 2003;9:1121-3.
9. Privat N, Laffont-Proust I, Faucheux BA, et al. Human prion diseases: from antibody screening to a standardized fast immunodiagnosis using automation. Mod Pathol 2008;21:140-9.
8
10. Levavasseur E, Laffont-Proust I, Morain E, et al. Regulating factors of PrP glycosylation in Creutzfeldt-Jakob disease--implications for the dissemination and the diagnosis of human prion strains. PloS one 2008;3:e2786.
11. Parchi P, Notari S, Weber P, et al. Inter-laboratory assessment of PrPSc typing in creutzfeldtjakob disease: a Western blot study within the NeuroPrion Consortium. Brain pathology 2009;19:384- 91.
12. McGuire LI, Poleggi A, Poggiolini I, et al. Cerebrospinal fluid real-time quaking-induced conversion is a robust and reliable test for sporadic creutzfeldt-jakob disease: An international study. Annals of neurology 2016;80:160-5.
snip...
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.
TUESDAY, AUGUST 12, 2008
Biosafety in Microbiological and Biomedical Laboratories Fifth Edition 2007 (occupational exposure to prion diseases)
re-Human Prion Diseases in the United States Posted by flounder on 01 Jan 2010 at 18:11 GMT
Research articles Health professions and risk of sporadic Creutzfeldt– Jakob disease, 1965 to 2010
15. Terry S. Singeltary Sr. Doctor Antonio Ruiz Villaespesa, pathologist and CJD researcher deceased because of Creutzfeldt-Jakob Disease SPAIN. 21 Apr 2009. [Accessed 11 Apr 2012]. In: Monitoring the occurrence of emerging forms of CJD [blog]. Available from:
SUNDAY, OCTOBER 27, 2013
A Kiss of a Prion: New Implications for Oral Transmissibility
THURSDAY, MAY 17, 2012
Iatrogenic Creutzfeldt-Jakob Disease, Final Assessment Volume 18, Number 6—June 2012
Thursday, April 12, 2012
Health professions and risk of sporadic Creutzfeldt–Jakob disease, 1965 to 2010
Eurosurveillance, Volume 17, Issue 15, 12 April 2012
Research articles
Saturday, January 16, 2010
*** Evidence For CJD TSE Transmission Via Endoscopes 1-24-3 re-Singeltary to Bramble et al
Evidence For CJD/TSE Transmission Via Endoscopes
From Terry S. Singletary, Sr flounder@wt.net 1-24-3
Terry S. Singeltary Sr., P.O. , Bacliff, Texas 77518 USA
Professor Michael Farthing wrote:
*** Louise Send this to Bramble (author) for a comment before we post. Michael
Wednesday, August 20, 2008
Tonometer disinfection practice in the United Kingdom: A national survey
Tuesday, August 12, 2008
Biosafety in Microbiological and Biomedical Laboratories Fifth Edition 2007 (occupational exposure to prion diseases)
Monday, December 31, 2007
Risk Assessment of Transmission of Sporadic Creutzfeldt-Jakob Disease in Endodontic Practice in Absence of Adequate Prion Inactivation
Subject: CJD: update for dental staff
Date: November 12, 2006 at 3:25 pm PST
1: Dent Update. 2006 Oct;33(8):454-6, 458-60.
CJD: update for dental staff.
MONDAY, JANUARY 14, 2019
Evaluation of iatrogenic risk of CJD transmission associated with Chronic Wasting Disease TSE Prion in Texas TAHC TPWD
FRIDAY, JANUARY 31, 2020
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF?
Confucius is confused again?
''The rare genetic forms of CJD (e.g., fCJD, GSS, FFI) share pathophysiological features with sCJD, and the transmission risk by blood components remains theoretical. Consequently, we recommend that establishments may stop asking prospective donors about having blood relatives with CJD.''
YET, vpspr, sporadic FFI, sporadic GSS, or the pending cases that can't be identified, are all now listed as sporadic CJD.
WHAT IF, sGSS, sFFI, are of an iatrogenic event from iatrogenic donor being from GSS or FFI?
what if vpspr is another strain of a different sporadic CJD, or familial? see;
7Includes 21 (21 from 2019) cases with type determination pending in which the diagnosis of vCJD has been excluded.
8The sporadic cases include 3831 cases of sporadic Creutzfeldt-Jakob disease (sCJD), 67 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 35 cases of sporadic Fatal Insomnia (sFI).
9Total does not include 264 Familial cases diagnosed by blood test only.
under new proposed guidelines ''we recommend that establishments may stop asking prospective donors about having blood relatives with CJD'' (of which i strongly oppose due to the fact sporadic cjd is not a single entity or a spontaneous event, never which have been proven), but under these guidelines, you will miss the vpspr, sgss, and sffi, because they are under sporadic cjd terminology, would you not?
The occurrence of the disease in a patient who had contact with cases of familial C.J.D., but was not genetically related, has been described in Chile (Galvez et al., 1980) and in France (Brown et al., 1979b). In Chile the patient was related by marriage, but with no consanguinity, and had social contact with subsequently affected family members for 13 years before developing the disease. The contact case in France also married into a family in which C.J.D. was prevalent and had close contact with an affected member. In neither instance did the spouse of the non-familial case have the disease. The case described in this report was similarly related to affected family members and social contact had occurred for 20 years prior to developing C.J.D. If contact transmission had occurred, the minimum transmission period would be 11 years. Contact between sporadic cases has not been described and it is remarkable that possible contact transmissions have all been with familial cases. No method of transmission by casual social contact has been suggested.
WHAT IF?
***The occurrence of contact cases raises the possibility that transmission in families may be effected by an unusually virulent strain of the agent.
snip...see full text here;
Sporadic Creutzfeldt-Jakob Disease in a Woman Married Into a Gerstmann-Sträussler-Scheinker Family: An Investigation of Prions Transmission via Microchimerism
Aušrinė Areškevičiūtė, MSc, Linea Cecilie Melchior, PhD, Helle Broholm, MD, Lars-Henrik Krarup, MD, PhD, Suzanne Granhøj Lindquist, MD, PhD, Peter Johansen, PhD, Neil McKenzie, PhD, Alison Green, PhD, Jørgen Erik Nielsen, MD, PhD, Henning Laursen, Dr.Med, Eva Løbner Lund, MD, PhD Journal of Neuropathology & Experimental Neurology, Volume 77, Issue 8, August 2018, Pages 673–684, https://doi.org/10.1093/jnen/nly043 Published: 07 June 2018
DISCUSSION
This is the first report of presumed sporadic CJD occurring in a person who married into a GSS family. The estimated prevalence of GSS is in the range of 2–5 per 100 million people worldwide, and the annual mortality rate for sCJD in Denmark is 1.46 per 1 million people (31). The population of Denmark consists of 5 740 185 individuals, and there are 2 registered GSS cases that belong to the same family. The Danish GSS family is only the thirty-fourth known GSS family in the world (32). One could assume that the risk for a Danish man with GSS to have a wife or a mother who would develop CJD in her seventies is as high as for any other man. On the basis of the mortality rate for sCJD, and assuming that the incidence of sCJD is the same among married and unmarried people, we could state that 1 man out of 684 932 men has a risk of marrying a woman who would develop CJD. However, in this case, the man a priori had GSS, which means that it would take 1 man out of 684 932 men with GSS for such a pairing to occur. Considering the worldwide rarity of GSS cases, the likelihood for co-occurrence of GSS and sCJD in one family is hence very low and warrants an investigation for the possible transmission of prions routes.
Volume 25, Number 1—January 2019
Research
Variable Protease-Sensitive Prionopathy Transmission to Bank Vol
Romolo Nonno1, Silvio Notari1, Michele Angelo Di Bari, Ignazio Cali, Laura Pirisinu, Claudia d’Agostino, Laura Cracco, Diane Kofskey, Ilaria Vanni, Jody Lavrich, Piero Parchi, Umberto Agrimi, and Pierluigi GambettiComments to Author
Author affiliations: Istituto Superiore di Sanità, Rome, Italy (R. Nonno, M.A. Di Bari, L. Pirisinu, C. d’Agostino, I. Vanni, U. Agrimi); Case Western Reserve University, Cleveland, Ohio, USA (S. Notari, I. Cali, L. Cracco, D. Kofskey, J. Lavrich, P. Gambetti); University of Bologna, Bologna, Italy (P. Parchi); Istituto delle Scienze Neurologiche di Bologna, Bologna (P. Parchi)
***> However, the VPSPr prion shares the multiplicity of the resPrPD electrophoretic bands with prions from a subset of inherited prion diseases referred to as Gerstmann-Sträussler-Scheinker disease (GSS), prompting the suggestion that VPSPr is the sporadic form of GSS (7,10). Furthermore, the presence of small amounts of sCJD-like 3-band resPrPD has also been signaled in VPSPr (6,11,12).
FRIDAY, JANUARY 10, 2014
vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ???
Greetings Friends, Neighbors, and Colleagues,
vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ???
Confucius is confused again.
I was just sitting and thinking about why there is no genetic link to some of these TSE prion sGSS, sFFi, and it’s really been working on my brain, and then it hit me today.
what if, vpspr, sgss, sffi, TSE prion disease, was a by-product from iatrogenic gss, ffi, familial type prion disease ???
it could explain the cases of no genetic link to the gss, ffi, familial type prion disease, to the family.
sporadic and familial is a red herring, in my opinion, and underestimation is spot on, due to the crude prehistoric diagnostic procedures and criteria and definition of a prion disease.
I say again, what if, iatrogenic, what if, with all these neurological disorders, with a common denominator that is increasingly showing up in the picture, called the prion.
I urge all scientist to come together here, with this as the utmost of importance about all these neurological disease that are increasingly showing up as a prion mechanism, to put on the front burners, the IATROGENIC aspect and the potential of transmission there from, with diseases/disease??? in question.
by definition, could they be a Transmissible Spongiform Encephalopathy TSE prion type disease, and if so, what are the iatrogenic chances of transmission?
this is very important, and should be at the forefront of research, and if proven, could be a monumental breakthrough in science and battle against the spreading of these disease/diseases.
sporadic CJD, along with new TSE prion disease in humans, of which the young are dying, of which long duration of illness from onset of symptoms to death have been documented, only to have a new name added to the pot of prion disease i.e. sporadic GSS, sporadic FFI, and or VPSPR. I only ponder how a familial type disease could be sporadic with no genetic link to any family member? when the USA is the only documented Country in the world to have documented two different cases of atypical H-type BSE, with one case being called atypical H-G BSE with the G meaning Genetic, with new science now showing that indeed atypical H-type BSE is very possible transmitted to cattle via oral transmission (Prion2014). sporadic CJD and VPSPR have been rising in Canada, USA, and the UK, with the same old excuse, better surveillance. You can only use that excuse for so many years, for so many decades, until one must conclude that CJD TSE prion cases are rising. a 48% incease in CJD in Canada is not just a blip or a reason of better surveillance, it is a mathematical rise in numbers. More and more we are seeing more humans exposed in various circumstance in the Hospital, Medical, Surgical arenas to the TSE Prion disease, and at the same time in North America, more and more humans are becoming exposed to the TSE prion disease via consumption of the TSE prion via deer and elk, cattle, sheep and goats, and for those that are exposed via or consumption, go on to further expose many others via the iatrogenic modes of transmission of the TSE prion disease i.e. friendly fire. I pondered this mode of transmission via the victims of sporadic FFI, sporadic GSS, could this be a iatrogenic event from someone sub-clinical with sFFI or sGSS ? what if?
Thursday, March 8, 2018
Familial human prion diseases associated with prion protein mutations Y226X and G131V are transmissible to transgenic mice expressing human prion protein
Furthermore, GSS A117V infected vole brains were able to induce the same disease phenotype in recipient voles within 3–4 months after challenge, proving that a prion agent propagated in the brains of infected animals. These findings imply that brains of GSS patients harbor infectious prions with transmissibility features similar to those found in other human and animal TSEs.
*** Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery ***
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
to date, the claim that 85% + of all human TSE Prion are spontaneous/sporadic event that just happens, in my opinion, has never been proven to date. it's a myth, just like the UKBSEnvCJD only there, where only typical c-BSE UK mad cow, is transmissible to humans, and all the rest is old cow disease or old people disease. remember, nvcjd has been documented in very old people as well, plus, it was postulated at the BSE Inquiry that, some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD. It remains a remote possibility that when older people contract CJD from BSE the resulting phenotype is like sporadic CJD and is distinct from the vCJD phenotype in younger people, and indeed today we find that;
SATURDAY, JUNE 23, 2018
Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification Volume 24, Number 7—July 2018
10. ZOONOTIC, ZOONOSIS, CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD DEER ELK DISEASE IN HUMANS, has it already happened, that should be the question...
''In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II)
EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ... See all authors
First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132 ;
also, see;
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data.
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison.
The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers.. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
snip...
The tissue distribution of infectivity in CWD‐infected cervids is now known to extend beyond CNS and lymphoid tissues. While the removal of these specific tissues from the food chain would reduce human dietary exposure to infectivity, exclusion from the food chain of the whole carcass of any infected animal would be required to eliminate human dietary exposure.
***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.
THURSDAY, FEBRUARY 15, 2018
Iatrogenic Creutzfeldt-Jakob disease with Amyloid-β pathology: an international study
http://creutzfeldt-jakob-disease.blogspot.com/2018/02/iatrogenic-creutzfeldt-jakob-disease.html
Iatrogenic Creutzfeldt-Jakob disease with Amyloid-β pathology: an international study
http://creutzfeldt-jakob-disease.blogspot.com/2018/02/iatrogenic-creutzfeldt-jakob-disease.html
WEDNESDAY, DECEMBER 04, 2019
Three Cases of Creutzfeldt-Jakob Disease with Visual Disturbances as Initial Manifestation
Friday, September 27, 2019
Prion disease and recommended procedures for flexible endoscope reprocessing – a review of policies worldwide and proposal for a simplified approach
THURSDAY, SEPTEMBER 26, 2019
Veterinary Biologics Guideline 3.32E: Guideline for minimising the risk of introducing transmissible spongiform encephalopathy prions and other infectious agents through veterinary biologics
SATURDAY, SEPTEMBER 21, 2019
National Variability in Prion Disease–Related Safety Policies for Neurologic Procedures
Wednesday, September 11, 2019
Is the re-use of sterilized implant abutments safe enough? (Implant abutment safety) iatrogenic TSE Prion
FRIDAY, SEPTEMBER 06, 2019
Disinfection of Multi-Use Ocular Equipment for Ophthalmological Procedures: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines
MONDAY, AUGUST 26, 2019
Creutzfeldt Jakob Disease CJD, TSE, Prion, Surveillance Update August 2019
SUNDAY, MARCH 10, 2019
National Prion Disease Pathology Surveillance Center Cases Examined¹ Updated Feb 1, 2019 Variably protease-sensitive prionopathy VPSPr
***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***
***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<***
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<***
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***
RESEARCH ARTICLE
Enhanced detection of prion infectivity from blood by preanalytical enrichment with peptoid-conjugated beads
Simone HornemannID1 *, Petra Schwarz1 , Elisabeth J. Rushing1 , Michael D. Connolly3 , Ronald N. Zuckermann3 , Alice Y. Yam2¤ , Adriano AguzziID1 * 1 Institute of Neuropathology, University of Zurich, Zurich, Switzerland, 2 Novartis Vaccines and Diagnostics Inc., Emeryville, California, United States of America, 3 Biological Nanostructures Facility, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America ¤ Current address: Sutro Biopharma, San Francisco, California, United States of America * Adriano.Aguzzi@usz.ch (AA); Simone.Hornemann@usz.ch (SH)
Abstract
Prions cause transmissible infectious diseases in humans and animals and have been found to be transmissible by blood transfusion even in the presymptomatic stage. However, the concentration of prions in body fluids such as blood and urine is extremely low; therefore, direct diagnostic tests on such specimens often yield false-negative results. Quantitative preanalytical prion enrichment may significantly improve the sensitivity of prion assays by concentrating trace amounts of prions from large volumes of body fluids. Here, we show that beads conjugated to positively charged peptoids not only captured PrP aggregates from plasma of prion-infected hamsters, but also adsorbed prion infectivity in both the symptomatic and preclinical stages of the disease. Bead absorbed prion infectivity efficiently transmitted disease to transgenic indicator mice. We found that the readout of the peptoidbased misfolded protein assay (MPA) correlates closely with prion infectivity in vivo, thereby validating the MPA as a simple, quantitative, and sensitive surrogate indicator of the presence of prions. The reliable and sensitive detection of prions in plasma will enable a wide variety of applications in basic prion research and diagnostics.
THURSDAY, JANUARY 30, 2020
Docket Number: FDA-2012-D-0307 Recommendations to Reduce the Possible Risk of Transmission of Creutzfeldt-Jakob Disease and Variant Creutzfeldt-Jakob Disease by Blood and Blood Components; Draft Guidance for Industry Draft Guidance for Industry Singeltary Submission
Tables of Cases Examined
National Prion Disease Pathology Surveillance Center Cases Examined¹ Updated December 9, 2019
Year Total Referrals² Prion Disease Sporadic Familial Iatrogenic vCJD
1999 & earlier 380 230 200 27 3 0
2000 145 102 90 12 0 0
2001 209 118 110 8 0 0
2002 241 144 124 18 2 0
2003 259 160 137 21 2 0
2004 316 181 164 16 0 1³
2005 327 178 156 21 1 0
2006 365 179 159 17 1 2⁴
2007 374 210 191 19 0 0
2008 384 221 205 16 0 0
2009 398 232 210 21 1 0
2010 401 246 218 28 0 0
2011 392 238 214 24 0 0
2012 413 244 221 23 0 0
2013 416 258 223 34 1 0
2014 355 208 185 21 1 1⁵
2015 402 264 244 20 0 0
2016 396 277 248 29 0 0
2017 375 266 247 19 0 0
2018 309 223 204 18 1 0
2019 351 220 183 16 0 0
TOTAL 72086 4399⁷ 3933⁸ 428⁹ 13 4
1Listed based on the year of death or, if not available, on year of referral;
2Cases with suspected prion disease for which brain tissue was submitted;
3Disease acquired in the United Kingdom;
4Disease acquired in the United Kingdom in one case and in Saudi Arabia in the other;
5Disease possibly acquired in a Middle Eastern or Eastern European country;
6Includes 20 cases in which the diagnosis is pending, and 19 inconclusive cases;
7Includes 21 (21 from 2019) cases with type determination pending in which the diagnosis of vCJD has been excluded.
8The sporadic cases include 3831 cases of sporadic Creutzfeldt-Jakob disease (sCJD), 67 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 35 cases of sporadic Fatal Insomnia (sFI).
9Total does not include 264 Familial cases diagnosed by blood test only.
FRIDAY, JANUARY 31, 2020
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
THURSDAY, SEPTEMBER 26, 2019
Veterinary Biologics Guideline 3.32E: Guideline for minimising the risk of introducing transmissible spongiform encephalopathy prions and other infectious agents through veterinary biologics
Sent: Sun, May 26, 2019 10:21 am Subject: Arguments for Alzheimer’s and Parkinson’s diseases caused by prions Stanley B. Prusiner
''From a large array of bioassays, we conclude that AD, PD, MSA, and the frontotemporal dementias, including PSP and CBD, are all prion diseases'' 11.
Arguments for Alzheimer’s and Parkinson’s diseases caused by prions Stanley B. Prusiner Institute of Neurodegenerative Diseases, and Professor of Neurology and Biochemistry, University of California San Francisco ABSTRACT Arguments for Alzheimer’s (AD) and Parkinson’s diseases (PD) being caused by prions continue to advance with new evidence. Findings in the brains of deceased AD patients argue that both Aβ and tau prions can be demonstrated by bioassays in cultured cells as well as in transgenic (Tg) mice. Likewise, studies of the brains of deceased MSA patients have been found to contain α-synuclein prions by bioassays in cultured cells and Tg mice. Conversely, the brains of AD patients do not contain α-synuclein prions, and the brains of MSA patients do not contain Aβ or tau prions. Additionally, while the brains of patients who died of either progressive supranuclear palsy (PSP) or corticobasal degeneration (CBD) contained tau prions, neither Aβ nor α-synuclein prions were detectable. Merely measuring the levels of Aβ, tau, and α-synuclein appears to give misleading information about the etiology and pathogenesis of neurodegenerative diseases (NDs). From a large array of bioassays, we conclude that AD, PD, MSA, and the frontotemporal dementias, including PSP and CBD, are all prion diseases. Our findings argue that changes in the conformations of Aβ, tau, and α-synuclein underlie the acquisition of prion infectivity in all of these NDs.
''From a large array of bioassays, we conclude that AD, PD, MSA, and the frontotemporal dementias, including PSP and CBD, are all prion diseases''
Published: 09 September 2015
Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy
Zane Jaunmuktane, Simon Mead, Matthew Ellis, Jonathan D. F. Wadsworth, Andrew J. Nicoll, Joanna Kenny, Francesca Launchbury, Jacqueline Linehan, Angela Richard-Loendt, A. Sarah Walker, Peter Rudge, John Collinge & Sebastian Brandner
>>> The only tenable public line will be that "more research is required’’ <<<
>>> possibility on a transmissible prion remains open<<<
O.K., so it’s about 23 years later, so somebody please tell me, when is "more research is required’’ enough time for evaluation ?
Re-Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy
Nature 525, 247?250 (10 September 2015) doi:10.1038/nature15369 Received 26 April 2015 Accepted 14 August 2015 Published online 09 September 2015 Updated online 11 September 2015 Erratum (October, 2015)
snip...see full Singeltary Nature comment here;
Alzheimer's disease
let's not forget the elephant in the room. curing Alzheimer's would be a great and wonderful thing, but for starters, why not start with the obvious, lets prove the cause or causes, and then start to stop that. think iatrogenic, friendly fire, or the pass it forward mode of transmission. think medical, surgical, dental, tissue, blood, related transmission. think transmissible spongiform encephalopathy aka tse prion disease aka mad cow type disease...
Commentary: Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy
Self-Propagative Replication of Ab Oligomers Suggests Potential Transmissibility in Alzheimer Disease
*** Singeltary comment PLoS ***
Alzheimer’s disease and Transmissible Spongiform Encephalopathy prion disease, Iatrogenic, what if ?
Posted by flounder on 05 Nov 2014 at 21:27 GMT
IN CONFIDENCE
5 NOVEMBER 1992
TRANSMISSION OF ALZHEIMER TYPE PLAQUES TO PRIMATES
[9. Whilst this matter is not at the moment directly concerned with the iatrogenic CJD cases from hgH, there remains a possibility of litigation here, and this presents an added complication.
There are also results to be made available shortly
(1) concerning a farmer with CJD who had BSE animals,
(2) on the possible transmissibility of Alzheimer’s and
(3) a CMO letter on prevention of iatrogenic CJD transmission in neurosurgery, all of which will serve to increase media interest.]
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA Diagnosis and Reporting of Creutzfeldt-Jakob Disease
To the Editor:
In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally..
Terry S. Singeltary, Sr Bacliff, Tex
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.
doi:10.1016/S1473-3099(03)00715-1 Copyright © 2003 Published by Elsevier Ltd. Newsdesk
Tracking spongiform encephalopathies in North America
Xavier Bosch
Available online 29 July 2003.
Volume 3, Issue 8, August 2003, Page 463
“My name is Terry S Singeltary Sr, and I live in Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and have been searching for answers ever since. What I have found is that we have not been told the truth. CWD in deer and elk is a small portion of a much bigger problem..” ............................
January 28, 2003; 60 (2) VIEWS & REVIEWS
Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States
Ermias D. Belay, Ryan A. Maddox, Pierluigi Gambetti, Lawrence B. Schonberger
First published January 28, 2003, DOI: https://doi.org/10.1212/01.WNL.0000036913.87823.D6
Abstract
Transmissible spongiform encephalopathies (TSEs) attracted increased attention in the mid-1980s because of the emergence among UK cattle of bovine spongiform encephalopathy (BSE), which has been shown to be transmitted to humans, causing a variant form of Creutzfeldt-Jakob disease (vCJD). The BSE outbreak has been reported in 19 European countries, Israel, and Japan, and human cases have so far been identified in four European countries, and more recently in a Canadian resident and a US resident who each lived in Britain during the BSE outbreak. To monitor the occurrence of emerging forms of CJD, such as vCJD, in the United States, the Centers for Disease Control and Prevention has been conducting surveillance for human TSEs through several mechanisms, including the establishment of the National Prion Disease Pathology Surveillance Center. Physicians are encouraged to maintain a high index of suspicion for vCJD and use the free services of the pathology center to assess the neuropathology of clinically diagnosed and suspected cases of CJD or other TSEs.
Received May 7, 2002. Accepted August 28, 2002.
RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States
Terry S. Singeltary, retired (medically)
Published March 26, 2003
26 March 2003
Terry S. Singeltary, retired (medically) CJD WATCH
I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc?
Reply to Singletary Ryan A. Maddox, MPH Other Contributors: Published March 26, 2003
Mr. Singletary raises several issues related to current Creutzfeldt- Jakob disease (CJD) surveillance activities. Although CJD is not a notifiable disease in most states, its unique characteristics, particularly its invariably fatal outcome within usually a year of onset, make routine mortality surveillance a useful surrogate for ongoing CJD surveillance.[1] In addition, because CJD is least accurately diagnosed early in the course of illness, notifiable-disease surveillance could be less accurate than, if not duplicative of, current mortality surveillance.[1] However, in states where making CJD officially notifiable would meaningfully facilitate the collection of data to monitor for variant CJD (vCJD) or other emerging prion diseases, CDC encourages the designation of CJD as a notifiable disease.[1] Moreover, CDC encourages physicians to report any diagnosed or suspected CJD cases that may be of special public health importance (e.g...., vCJD, iatrogenic CJD, unusual CJD clusters).
As noted in our article, strong evidence is lacking for a causal link between chronic wasting disease (CWD) of deer and elk and human disease,[2] but only limited data seeking such evidence exist. Overall, the previously published case-control studies that have evaluated environmental sources of infection for sporadic CJD have not consistently identified strong evidence for a common risk factor.[3] However, the power of a case-control study to detect a rare cause of CJD is limited, particularly given the relatively small number of subjects generally involved and its long incubation period, which may last for decades. Because only a very small proportion of the US population has been exposed to CWD, a targeted surveillance and investigation of unusual cases or case clusters of prion diseases among persons at increased risk of exposure to CWD is a more efficient approach to detecting the possible transmission of CWD to humans. In collaboration with appropriate local and state health departments and the National Prion Disease Pathology Surveillance Center, CDC is facilitating or conducting such surveillance and case- investigations, including related laboratory studies to characterize CJD and CWD prions.
Mr. Singletary also expresses concern over a recent publication by Asante and colleagues indicating the possibility that some sporadic CJD cases may be attributable to bovine spongiform encephalopathy (BSE).[4] The authors reported that transgenic mice expressing human prion protein homozygous for methionine at codon 129, when inoculated with BSE prions, developed a molecular phenotype consistent with a subtype of sporadic CJD. Although the authors implied that BSE might cause a sporadic CJD-like illness among persons homozygous for methionine, the results of their research with mice do not necessarily directly apply to the transmission of BSE to humans. If BSE causes a sporadic CJD-like illness in humans, an increase in sporadic CJD cases would be expected to first occur in the United Kingdom, where the vast majority of vCJD cases have been reported. In the United Kingdom during 1997 through 2002, however, the overall average annual mortality rate for sporadic CJD was not elevated; it was about 1 case per million population per year. In addition, during this most recent 6-year period following the first published description of vCJD in 1996, there was no increasing trend in the reported annual number of UK sporadic CJD deaths.[3, 5] Furthermore, surveillance in the UK has shown no increase in the proportion of sporadic CJD cases that are homozygous for methionine (Will RG, National CJD Surveillance Unit, United Kingdom, 2003; personal communication)..
References
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Diagnosis and reporting of Creutzfeldt-Jakob disease. JAMA 2001;285:733-734.
2. Belay ED, Maddox RA, Gambetti P, Schonberger LB. Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States. Neurology 2003;60:176-181.
3. Belay ED. Transmissible spongiform encephalopathies in humans. Annu Rev Microbiol 1999;53:283-314.
4. Asante EA, Linehan JM, Desbruslais M, et al. BSE prions propagate as either variant CJD-like or sporadic CJD-like prion strains in transgenic mice expressing human prion protein. EMBO J 2002;21:6358-6366.
5. The UK Creutzfeldt-Jakob Disease Surveillance Unit. CJD statistics. Available at: http://www.cjd.ed.ac.uk/figures.htm. Accessed February 18, 2003.
Competing Interests: None declared.
Volume 2: Science
4. The link between BSE and vCJD
Summary 4.29 The evidence discussed above that vCJD is caused by BSE seems overwhelming. Uncertainties exist about the cause of CJD in farmers, their wives and in several abattoir workers. It seems that farmers at least might be at higher risk than others in the general population. 1 Increased ascertainment (ie, increased identification of cases as a result of greater awareness of the condition) seems unlikely, as other groups exposed to risk, such as butchers and veterinarians, do not appear to have been affected. The CJD in farmers seems to be similar to other sporadic CJD in age of onset, in respect to glycosylation patterns, and in strain-typing in experimental mice. Some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD.
***>It remains a remote possibility that when older people contract CJD from BSE the resulting phenotype is like sporadic CJD and is distinct from the vCJD phenotype in younger people...end
BSE INQUIRY
SATURDAY, JUNE 23, 2018
CDC
***> Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification
Volume 24, Number 7—July 2018 Dispatch
THURSDAY, JULY 02, 2020
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
SATURDAY, AUGUST 1, 2020
Eliminating Spiked Bovine Spongiform Encephalopathy Agent Activity from Heparin Volume 26, Number 10—October 2020
However most Iatrogenic CJD cases are nothing more than sporadic CJD, until the source is proven, then it becomes Iatrogenic. An oxymoron of sorts, because all sporadic CJD is, are multiple forms, or strains, or phenotypes of Creutzfeldt Jakob Disease, that the route and source and species have not been confirmed and or documented...
Singeltary et al
2019
friendly fire, pass it forward, they call it iatrogenic cjd, or what i call 'tse prion poker', are you all in $$$
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd, PLUS, SPORADIC CJD HAS NOW BEEN LINKED TO ATYPICAL AND TYPICAL BSE, SCRAPIE, AND NOW CWD. ...terry
FRIDAY, SEPTEMBER 06, 2019
Disinfection of Multi-Use Ocular Equipment for Ophthalmological Procedures: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, provern, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd, PLUS, SPORADIC CJD HAS NOW BEEN LINKED TO ATYPICAL AND TYPICAL BSE, SCRAPIE, AND NOW CWD. ...terry
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
12:34 PM
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