PHNB OVERSIGHT COMMITTEE REPORT ON Potential Neurological Syndrome of Unknown Cause February 22, 2022 Executive Summary
News Release
Health
Clinical review finds no evidence of a cluster of a neurological syndrome of unknown cause
24 February 2022
FREDERICTON (GNB) – A final investigation report into a potential cluster of a neurological syndrome of unknown cause was released today, offering several recommendations and potential solutions to improve processes related to surveillance and outbreak investigations.
“There can be no doubt these patients are seriously ill,” said Health Minister Dorothy Shephard. “This report means they are ill with other serious diseases, injuries or conditions. The committee noted that some of the patients were in urgent need of immediate followup assessment and care. I am confident our province’s specialists and other health-care providers are fully capable of providing that care, but I advised the patients and their families today that they are welcome to seek a second opinion through a referral from their primary care provider.”
Shephard accepted both Public Health New Brunswick’s final report and an oversight committee report that concluded that no such syndrome exists in New Brunswick.
The oversight committee includes six neurologists, one co-chair from each of the regional health authorities, and one representative from Public Health. It was established last June to provide independent clinical oversight and to make recommendations regarding the 48 cases that were initially identified as part of the cluster.
The clinical review found that each patient displayed symptoms that varied significantly and there is no evidence of a shared common illness or a syndrome of unknown cause. The full report is available online. Public Health released its own report, which is also available online and makes several recommendations to improve the way potential new diseases are reported and investigated.
Dr. Jennifer Russell, chief medical officer of health, said that Public Health is making recommendations that requires regulatory changes and action from levels of government.
“We have made several recommendations to ensure a situation like this does not occur again,” said Russell
Public Health New Brunswick’s recommendations include:
· In the future, Public Health New Brunswick may request a clinical review of cases by a second specialist physician prior to including cases in a cluster of unknown cause. If the two physicians do not agree, the case should be presented to a board of specialty doctors or an oversight committee for a decision.
· The Reporting and Diseases Regulation under the Public Health Act should be amended to require a suspect case of any existing or new variant of human or animal prion disease be reported to Public Health New Brunswick.
· Public Health New Brunswick should continue to build on collaborations with the Public Health Agency of Canada and other federal and provincial partners to improve and modernize the national Creutzfeldt/Jakob Disease (CJD) surveillance system and to establish or improve processes related to outbreak investigations that may arise from this surveillance, including those where prion disease has been excluded. To this end, it supports the creation of a federal, provincial and territorial working group that would support this review.
“The Public Health Agency of Canada is pleased that the investigation has come to a close and supports the investigation’s findings,” said Dr. Howard Njoo, Canada’s deputy chief public health officer. “Over the course of the investigation, the Public Health Agency of Canada provided specialized diagnostic laboratory and neuropathology services and expertise to rule out prion disease, and, through the Canadian Field Epidemiology Program, deployed several epidemiologists and assisted in the development of the epidemiological questionnaire.”
Public Health is recommending all patients who were advised they may have a neurological syndrome of unknown cause, or who may have a neurodegenerative disorder, to contact their primary care provider for a referral to the Moncton Interdisciplinary Neurodegenerative Diseases Clinic or another specialist physician.
The clinic is a cross-specialty, collaborative, precision medicine facility for neurocognitive disorders affecting adults. Its primary goal is to assess, diagnose and provide ongoing care and treatment to patients with progressive neurodegenerative diseases to improve their quality of life and provide family support.
24-02-22
OVERSIGHT COMMITTEE REPORT ON
Potential Neurological Syndrome of Unknown Cause
February 22, 2022
Executive Summary
In the context of a public health investigation led by Public Health New Brunswick (PHNB), the oversight committee, created expressly to provide independent expert oversight and recommendations regarding cases that were identified as part of a cluster with a potential neurological syndrome of unknown cause, presented its findings.
Between August 2021 and February 2022, the committee conducted case reviews, including chart reviews and secondary reviews, for the 48 individuals identified as members of the cluster. These cases were between 18 and 85 years of age (median = 57 years, SD = 18 years), and half were female (24 cases). Most of them were reported to be living in New Brunswick health zones 1 (73%) and 6 (21%) at the time of their referral to the Creutzfeldt-Jakob Disease Surveillance System (CJDSS), which identified them as members of the cluster.
During the in-depth clinical reviews, cases were randomly allocated to pairs of neurologists, who reviewed independently and then presented and discussed their findings with the full committee consisting of six neurologists, co-chairs from Horizon Health Network (HHN) and Vitalité Health Network (VHN), and a Medical Officer of Health acting as a liaison with PHNB.
The committee found that out of 48 cases, none fulfilled the full criteria of the case definition. In light of these findings, the committee concluded that although some of the cases have presentations with unusual symptomology, they do not appear to have a common illness with an unknown etiology and there is no evidence of a cluster of neurological syndrome of unknown cause.
Investigation into a Neurological Syndrome of Unknown Cause: An Epidemiological Summary of Enhanced Surveillance Interviews
Epidemiology and Surveillance Branch Public Health New Brunswick
Date: October 26th, 2021
Summary
As of April 30, 2021, there were a total 48 individuals who were identified as having a potential neurological syndrome of unknown cause in New Brunswick. These individuals were referred to the CJDSS by three neurologists from New Brunswick for further testing, with all but two cases referred by the same neurologist. The first case was referred in 2015, followed by 12 cases in 2019, 25 cases in 2020, and 10 cases in 2021. The case from 2015 was included retroactively at the clinician’s suggestion, due to similarities in clinical presentation and lack of a confirmed diagnosis, when the existence of the cluster was tentatively recognized in early 2020. To date, none of these individuals have tested positively for known forms of human prion diseases.
The cluster of individuals with neurological symptoms was identified by the main referring neurologist through consultation with the Creutzfeldt-Jakob Disease Surveillance System (CJDSS). The CJDSS is managed by the Public Health Agency of Canada (PHAC) and performs nationwide monitoring for prion diseases that cause neurologic manifestations in humans, such as Creutzfeldt-Jakob Disease (CJD). These diseases provoke changes in the brain that can cause rapidly developing dementia, confusion, difficulties with movement and speaking, hallucinations, muscle stiffness and fatigue.
The potential syndrome appears to be limited to New Brunswick and the majority of the interviewed cases were reported to be living in Southeastern and Northeastern parts of the province at the time their symptoms started. The geographic distribution of the cases may have been influenced by the catchment area of the referring neurologists.
Cases were asked about their food exposures and surrounding environment. The most common exposures were lobsters, wild berries, scallops, shrimps and prawns, regular interactions with a pet in their household, spending time near an ocean, and spending time near an industrial site. Details regarding exposures are presented in the Results section and in Appendix A: Extended Tables. All exposures were self-reported by the respondents and have not been confirmed by clinical or diagnostic information.
Some of the identified exposures appear to be common among the cases under investigation. However, none of these are deemed to be concerning upon further analysis of the enhanced surveillance interview responses. Many of the exposures are typical of the region, which is strongly influenced by Maritime cultural practices. For example, most cases reported consuming lobsters only a few times per year—which is well below the recommended consumption limit issued by Health Canada. In addition, lobster consumption has not been identified as a cause of illness by NBPS or the Public Health Agency of Canada in the past 10 years. As for the consumption of wild berries does not appear, these are not linked to any particular source. Furthermore, there is no evidence from this report that a particular food, such as lobster, wild berries or moose, is linked to the development of neurological symptoms, as more cases would have been identified within New Brunswick and in neighbouring provinces or states. Clinical and diagnostic information is currently being reviewed by the Oversight Committee and may help determine whether there are alternate diagnoses for the individuals included in this potential cluster or whether more investigation is required.
Conclusion
Based on the findings of this report, there are no specific behaviours, foods, or environmental exposures that can be identified as potential risk factors with regards to the identified cluster of cases with a potential neurological syndrome of unknown cause. As such, residents should feel confident that they are not considered to be at risk of any food or environmental exposures within the province.
PHNB has adopted a thorough, transparent, and open approach and has considered a wide range of hypotheses that include food safety, environmental factors, and lifestyle practices. The surveillance interviews with individuals associated with this potential neurological syndrome is a vital first step towards understanding more about this cluster of cases. The investigation into this cluster of cases is still active and PHNB continues to collaborate with local and national subject matter experts and healthcare providers to identify potential risk factors and prevention measures for this potential syndrome. Further epidemiological research, such as an observational study (e.g., case-control study), a second round of interviews or further testing, may be required once the review of the clinical investigations is completed by the Oversight Committee.
see full investigation review here;
FRIDAY, DECEMBER 24, 2021
Creutzfeldt Jakob Disease CJD TSE Prion Update December 25, 2021
Terry S. Singeltary Sr.