The molecular epidemiology of hepatitis E virus genotype 3 in Canada.

Autochthonous hepatitis E virus (HEV) infection is increasingly reported in industrialized countries and is mostly associated with zoonotic HEV genotype 3 (HEV-3). In this study, we examined the molecular epidemiology of 63 human clinical HEV-3 isolates in Canada between 2014 and 2022. Fifty-five samples were IgM positive, 45 samples were IgG positive and 44 were IgM and IgG positive. The majority of the isolates belong to the subtypes 3a, 3b, and 3j, with high sequence homology to Canadian swine and pork isolates. There were a few isolates that clustered with subtypes 3c, 3e, 3f, 3h, and 3g, and an isolate from chronic infection with a rabbit strain (3ra). Previous studies have demonstrated that the isolates from pork products and swine from Canada belong to subtypes 3a and 3b, therefore, domestic swine HEV is likely responsible for the majority of clinical HEV cases in Canada and further support the hypothesis that swine serve as the main reservoirs for HEV-3 infections. Understanding the associated risk of zoonotic HEV infection requires the establishment of sustainable surveillance strategies at the interface between humans, animals, and the environment within a One-Health framework.

Ongoing Gaps in the Hepatitis C Care Cascade during the Direct-Acting Antiviral Era in a Large Retrospective Cohort in Canada: A Population-Based Study.

To achieve hepatitis C virus (HCV) elimination, high uptake along the care cascade steps for all will be necessary. We mapped engagement with the care cascade overall and among priority groups in the post-direct-acting antivirals (DAAs) period and assessed if this changed relative to pre-DAAs. We created a population-based cohort of all reported HCV diagnoses in Quebec (1990-2018) and constructed the care cascade [antibody diagnosed, RNA tested, RNA positive, genotyped, treated, sustained virologic response (SVR)] in 2013 and 2018. Characteristics associated with RNA testing and treatment initiation were investigated using marginal logistic models via generalized estimating equations. Of the 31,439 individuals HCV-diagnosed in Quebec since 1990 and alive as of 2018, there was significant progress in engagement with the care cascade post- vs. pre-DAAs; 86% vs. 77% were RNA-tested, and 64% vs. 40% initiated treatment. As of 2018, a higher risk of not being RNA-tested or treated was observed among individuals born <1945 vs. >1965 [hazard ratio (HR); 95% CI; 1.35 (1.16-1.57)], those with material and social deprivation [1.21 (1.06-1.38)], and those with alcohol use disorder [1.21 (1.08-1.360]. Overall, non-immigrants had lower rates of RNA testing [0.76 (0.67-0.85)] and treatment initiation [0.63 (0.57-0.70)] than immigrants. As of 2018, PWID had a lower risk of not being RNA tested [0.67 (0.61-0.85)] but a similar risk of not being treated, compared to non-PWID. Engagement in the HCV care cascade have improved in the post-DAA era, but inequities remain. Vulnerable subgroups, including certain older immigrants, were less likely to have received RNA testing or treatment as of 2018 and would benefit from focused interventions to strengthen these steps.

Hepatitis B virus genotype surveillance in Canadian blood donors and a referred patient population, 2016-2021.

BACKGROUND AND OBJECTIVES: Hepatitis B virus (HBV) genotypes (A-H) have a distinct geographic distribution and are highly associated with the country of birth. Canada has experienced increased immigration over the past decade, primarily from regions where HBV is endemic. This study investigated the proportions and trends of HBV genotypes within blood donor and clinical populations of Canada over the period 2016-2021. MATERIALS AND METHODS: Study samples involved two cohorts: (1) Canadian blood donors (n = 246) deferred from donation due to HBV test positivity and (2) chronic HBV patients from across Canada (clinically referred population, n = 3539). Plasma or serum was extracted, and the surface antigen and/or polymerase-coding region was amplified and sequenced to determine genotype by phylogenetic analysis. RESULTS: Six (A-E, G) and eight (A-H) HBV genotypes were detected among deferred blood donors and the clinically referred population, respectively. Differences in HBV genotype proportions between the two cohorts were observed across Canada. Males comprised most of the referred population among genotypes A-E (p < 0.0001), except for genotypes B and C. The median age was younger among blood donors (36 years [range 17-72]) compared with the referred population (41 years [range 0-99]). Distinct trends of increasing (E, referred; B, blood donor) and decreasing genotype prevalence were observed over the study period. CONCLUSION: HBV genotypes in Canada are highly diverse, suggesting a large immigrant population. Observed trends in genotype prevalence and proportional differences among cohorts imply shifts among the HBV-infected population of Canada, which warrants continued surveillance.

Using medical storytelling to communicate problems and solutions in the low back pain conundrum: an evidence-based tale of twins.

OBJECTIVES: Low back pain (LBP) is the number one cause of disability world-wide. It is also the most expensive area in healthcare. Patient-centered innovations are needed. This paper uses medical storytelling to illustrate the common problems that often lead to unnecessary suffering for patients, and costs to society. We present innovative solutions, including narrative interventions. METHODS: We use medical storytelling to present a scenario in which hypothetical twin patients with identical LBP episodes enter the healthcare system, with one twin managed in an appropriate manner, and the other inappropriately. RESULTS: One twin becomes a chronic LBP sufferer, while the other experiences quick resolution, despite identical conditions. Recommendations are made to de-implement inappropriate action and to implement a more productive approach. CONCLUSIONS: Many patients with LBP descend into chronic pain. This is rarely inevitable based on clinical factors. Much of chronic LBP results from how the condition is handled within the healthcare system. Medical narrative may be one innovation to illustrate the problem of current LBP management, recommend solutions and foster changes in clinical behavior. PRACTICAL IMPLICATIONS: The starkly different outcomes for each identical twin are illustrated. Recommendations are made for reframing the situation to de-implement the inappropriate and to implement a more appropriate approach.

A population-based study of reported hepatitis C diagnoses from 1998 to 2018 in immigrants and nonimmigrants in Quebec, Canada.

Immigrants living in low hepatitis C (HCV) prevalence countries bear a disproportionate HCV burden, but there are limited HCV population-based studies focussed on this population. We estimated rates and trends of reported HCV diagnoses over a 20-year period in Quebec, Canada, to investigate subgroups with the highest rates and changes over time. A population-based cohort of all reported HCV diagnoses in Quebec (1998-2018) linked to health administrative and immigration databases. HCV rates, rate ratios (RR) and trends overall and stratified by immigrant status and country of birth were estimated using Poisson regression. Among 38,348 HCV diagnoses, 14% occurred in immigrants, a median of 7.5 years after arrival. The average annual HCV rate/100,000 decreased for immigrants and nonimmigrants, but the risk (RR) among immigrants increased over the study period [35.7 vs. 34.5 (RR = 1.03) and 18.4 vs. 12.7 (1.45) between 1998-2008 and 2009-2018]. Immigrants from middle-income Europe & Central Asia [55.8 (RR = 4.39)], sub-Saharan Africa [51.7 (RR = 4.06)] and South Asia [32.8 (RR = 2.58)] had the highest rates between 2009 and 2018. Annual HCV rates decreased more slowly among immigrants vs. nonimmigrants (-5.9% vs. -8.9%, p < 0.001), resulting in a 2.5-fold (9%-21%) increase in the proportion of HCV diagnoses among immigrants (1998-2018). The slower decline in HCV rates among immigrants over the study period highlights the need for targeted screening for this population, particularly those from sub-Saharan Africa, Asia and middle-income Europe. These data can inform micro-elimination efforts in Canada and other low-HCV-prevalence countries.

The primary spine practitioner as a new role in healthcare systems in North America.

BACKGROUND: In an article published in 2011, we discussed the need for a new role in health care systems, referred to as the Primary Spine Practitioner (PSP). The PSP model was proposed to help bring order to the chaotic nature of spine care. Over the past decade, several efforts have applied the concepts presented in that article. The purpose of the present article is to discuss the ongoing need for the PSP role in health care systems, present persistent barriers, report several examples of the model in action, and propose future strategies. MAIN BODY: The management of spine related disorders, defined here as various disorders related to the spine that produce axial pain, radiculopathy and other related symptoms, has received significant international attention due to the high costs and relatively poor outcomes in spine care. The PSP model seeks to bring increased efficiency, effectiveness and value. The barriers to the implementation of this model have been significant, and responses to these barriers are discussed. Several examples of PSP integration are presented, including clinic systems in primary care and hospital environments, underserved areas around the world and a program designed to reduce surgical waiting lists. Future strategies are proposed for overcoming the continuing barriers to PSP implementation in health care systems more broadly. CONCLUSION: Significant progress has been made toward integrating the PSP role into health care systems over the past 10 years. However, much work remains. This requires substantial effort on the part of those involved in the development and implementation of the PSP model, in addition to support from various stakeholders who will benefit from the proposed improvements in spine care.

Invasive Treatments for Low Back Disorders.

OBJECTIVE: This abbreviated version of the American College of Occupational and Environmental Medicine's Low Back Disorders guideline reviews the evidence and recommendations developed for invasive treatments used to manage low back disorders. METHODS: Comprehensive systematic literature reviews were accomplished with article abstraction, critiquing, grading, evidence table compilation, and guideline finalization by a multidisciplinary expert panel and extensive peer-review to develop evidence-based guidance. Consensus recommendations were formulated when evidence was lacking and often relied on analogy to other disorders for which evidence exists. A total of 47 high-quality and 321 moderate-quality trials were identified for invasive management of low back disorders. RESULTS: Guidance has been developed for the invasive management of acute, subacute, and chronic low back disorders and rehabilitation. This includes 49 specific recommendations. CONCLUSION: Quality evidence should guide invasive treatment for all phases of managing low back disorders.

Non-Invasive and Minimally Invasive Management of Low Back Disorders.

OBJECTIVE: This abbreviated version of the American College of Occupational and Environmental Medicine's (ACOEM) Low Back Disorders Guideline reviews the evidence and recommendations developed for non-invasive and minimally invasive management of low back disorders. METHODS: Systematic literature reviews were accomplished with article abstraction, critiquing, grading, evidence table compilation, and guideline finalization by a multidisciplinary expert panel and extensive peer-review to develop evidence-based guidance. Consensus recommendations were formulated when evidence was lacking. A total of 70 high-quality and 564 moderate-quality trials were identified for non-invasive low back disorders. Detailed algorithms were developed. RESULTS: Guidance has been developed for the management of acute, subacute, and chronic low back disorders and rehabilitation. This includes 121 specific recommendations. CONCLUSION: Quality evidence should guide treatment for all phases of managing low back disorders.

Diagnostic Tests for Low Back Disorders.

OBJECTIVE: The aim of this study was to summarize evidence-based diagnostic guidelines for low back disorders. METHODS: A comprehensive literature review was conducted. A total of 101 articles of high or moderate quality addressing low back disorders diagnostic evaluation met the inclusion criteria. Evidence-based recommendations were developed and graded from (A) to (C) in favor and against the specific diagnostic test, with (A) level having the highest quality body of literature. Expert consensus was employed for insufficient evidence (I) to develop consensus guidance. RESULTS: Recommendations are given for these diagnostic tests: functional capacity evaluations, roentgenograms (x-rays), magnetic resonance imaging (MRI), computerized tomography, myelography, bone scans, single proton emission computed tomography, electromyography, surface electromyography, ultrasound, thermography, fluoroscopy, videofluoroscopy, lumbar discography, MRI discography, and myeloscopy. CONCLUSION: Diagnostic testing is not indicated for the majority of patients with low back pain.

Comparative Clinical Effectiveness of Nonsurgical Treatment Methods in Patients With Lumbar Spinal Stenosis: A Randomized Clinical Trial.

Importance: Lumbar spinal stenosis (LSS) is the most common reason for spine surgery in older US adults. There is an evidence gap about nonsurgical LSS treatment options. Objective: To explore the comparative clinical effectiveness of 3 nonsurgical interventions for patients with LSS. Design, Setting, and Participants: Three-arm randomized clinical trial of 3 years' duration (November 2013 to June 2016). Analysis began in August 2016. All interventions were delivered during 6 weeks with follow-up at 2 months and 6 months at an outpatient research clinic. Patients older than 60 years with LSS were recruited from the general public. Eligibility required anatomical evidence of central canal and/or lateral recess stenosis (magnetic resonance imaging/computed tomography) and clinical symptoms associated with LSS (neurogenic claudication; less symptoms with flexion). Analysis was intention to treat. Interventions: Medical care, group exercise, and manual therapy/individualized exercise. Medical care consisted of medications and/or epidural injections provided by a physiatrist. Group exercise classes were supervised by fitness instructors in senior community centers. Manual therapy/individualized exercise consisted of spinal mobilization, stretches, and strength training provided by chiropractors and physical therapists. Main Outcomes and Measures: Primary outcomes were between-group differences at 2 months in self-reported symptoms and physical function measured by the Swiss Spinal Stenosis questionnaire (score range, 12-55) and a measure of walking capacity using the self-paced walking test (meters walked for 0 to 30 minutes). Results: A total of 259 participants (mean [SD] age, 72.4 [7.8] years; 137 women [52.9%]) were allocated to medical care (88 [34.0%]), group exercise (84 [32.4%]), or manual therapy/individualized exercise (87 [33.6%]). Adjusted between-group analyses at 2 months showed manual therapy/individualized exercise had greater improvement of symptoms and physical function compared with medical care (-2.0; 95% CI, -3.6 to -0.4) or group exercise (-2.4; 95% CI, -4.1 to -0.8). Manual therapy/individualized exercise had a greater proportion of responders (≥30% improvement) in symptoms and physical function (20%) and walking capacity (65.3%) at 2 months compared with medical care (7.6% and 48.7%, respectively) or group exercise (3.0% and 46.2%, respectively). At 6 months, there were no between-group differences in mean outcome scores or responder rates. Conclusions and Relevance: A combination of manual therapy/individualized exercise provides greater short-term improvement in symptoms and physical function and walking capacity than medical care or group exercises, although all 3 interventions were associated with improvements in long-term walking capacity. Trial Registration: ClinicalTrials.gov Identifier: NCT01943435.

Highly Diverse Hepatitis C Strains Detected in Sub-Saharan Africa Have Unknown Susceptibility to Direct-Acting Antiviral Treatments.

The global plan to eradicate hepatitis C virus (HCV) led by the World Health Organization outlines the use of highly effective direct-acting antiviral drugs (DAAs) to achieve elimination by 2030. Identifying individuals with active disease and investigation of the breadth of diversity of the virus in sub-Saharan Africa (SSA) is essential as genotypes in this region (where very few clinical trials have been carried out) are distinct from those found in other parts of the world. We undertook a population-based, nested case-control study in Uganda and obtained additional samples from the Democratic Republic of Congo (DRC) to estimate the prevalence of HCV, assess strategies for disease detection using serological and molecular techniques, and characterize genetic diversity of the virus. Using next-generation and Sanger sequencing, we aimed to identify strains circulating in East and Central Africa. A total of 7,751 Ugandan patients were initially screened for HCV, and 20 PCR-positive samples were obtained for sequencing. Serological assays were found to vary significantly in specificity for HCV. HCV strains detected in Uganda included genotype (g) 4k, g4p, g4q, and g4s and a newly identified unassigned g7 HCV strain. Two additional unassigned g7 strains were identified in patients originating from DRC (one partial and one full open reading frame sequence). These g4 and g7 strains contain nonstructural (ns) protein 3 and 5A polymorphisms associated with resistance to DAAs in other genotypes. Clinical studies are therefore indicated to investigate treatment response in infected patients. Conclusion: Although HCV prevalence and genotypes have been well characterized in patients in well-resourced countries, clinical trials are urgently required in SSA, where highly diverse g4 and g7 strains circulate.

Acute hepatitis B virus infection with delayed appearance of hepatitis B core antibody in an immunocompromised patient: a case report.

BACKGROUND: Despite the introduction of universal hepatitis B immunization programs worldwide, outbreaks of acute infection still occur in unimmunized individuals. A timely diagnosis of hepatitis B is necessary to ensure adequate clinical care and public health interventions that will reduce transmission. Yet, interpretation of hepatitis B serological markers can be complex. We present a case of hepatitis B with atypical markers, including delayed appearance of hepatitis B core antibody. CASE PRESENTATION: A 62-year-old white woman was identified as a sexual contact of a male individual with acute hepatitis B virus infection. She had a history of recurrent low-grade non-Hodgkin lymphoma and had recently received immunosuppressive therapy. At baseline she had a negative serology and received three double doses (40 µg) of Engerix-B vaccine (hepatitis B vaccine) with a 0-month, 1-month, and 6-month schedule. One month following the last dose, hepatitis B surface antigen was positive in the absence of hepatitis B core antibody. The only sign of infection was a slight elevation of alanine aminotransferase enzymes a few months after first sexual contacts with the male individual. Hepatitis B virus infection was later confirmed despite the absence of hepatitis B core antibody. The development of hepatitis B core antibody was finally noted more than 6 months after the first positive hepatitis B surface antigen and more than 12 months after elevation of alanine aminotransferase enzymes. Immunosuppression including rituximab treatment was the most likely explanation for this serological profile. On her last medical assessment, she had not developed HBeAg seroconversion despite lower hepatitis B virus deoxyribonucleic acid levels with tenofovir treatment. CONCLUSIONS: When confronted with positive hepatitis B surface antigen in the absence of hepatitis B core antibody, consideration should be given to the possibility of both acute and persistent infection particularly in the setting of immunosuppression so that appropriate clinical management and public health interventions can take place. Given the increasing use of biologicals such as anti-tumor necrosis factor therapies either alone or with other immunosuppressive agents, this phenomenon may be encountered more frequently.

Spine Care as a Framework for the Chiropractic Identity.

OBJECTIVE: The purpose of this commentary is to provide an argument for the role and identity of chiropractors as spine care providers within the context of the greater health care system. DISCUSSION: Surveys of the general public and chiropractors indicate that the majority of patients seek chiropractic services for back and neck pain. Insurance company utilization data confirm these findings. Regulatory and legal language found in chiropractic practice acts reveals that most jurisdictions define the chiropractic scope of practice as based on a foundation of spine care. Educational accrediting and testing organizations have been shaped around a chiropractic education that produces graduates who focus on the diagnosis and treatment of spine and musculoskeletal disorders. Spine care is thus the common denominator and theme throughout all aspects of chiropractic practice, legislation, and education globally. CONCLUSION: Although the chiropractic profession may debate internally about its professional identity, the chiropractic identity seems to have already been established by society, practice, legislation, and education as a profession of health care providers whose area of expertise is spine care.

Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? No.

BACKGROUND: The purported relationship between cervical manipulative therapy (CMT) and stroke related to vertebral artery dissection (VAD) has been debated for several decades. A large number of publications, from case reports to case-control studies, have investigated this relationship. A recent article suggested that case misclassification in the case-control studies on this topic resulted in biased odds ratios in those studies. DISCUSSION: Given its rarity, the best epidemiologic research design for investigating the relationship between CMT and VAD is the case-control study. The addition of a case-crossover aspect further strengthens the scientific rigor of such studies by reducing bias. The most recent studies investigating the relationship between CMT and VAD indicate that the relationship is not causal. In fact, a comparable relationship between vertebral artery-related stroke and visits to a primary care physician has been observed. The statistical association between visits to chiropractors and VAD can best be explained as resulting from a patient with early manifestation of VAD (neck pain with or without headache) seeking the services of a chiropractor for relief of this pain. Sometime after the visit the patient experiences VAD-related stroke that would have occurred regardless of the care received. This explanation has been challenged by a recent article putting forth the argument that case misclassification is likely to have biased the odds ratios of the case-control studies that have investigated the association between CMT and vertebral artery related stroke. The challenge particularly focused on one of the case-control studies, which had concluded that the association between CMT and vertebral artery related stroke was not causal. It was suggested by the authors of the recent article that misclassification led to an underestimation of risk. We argue that the information presented in that article does not support the authors' claim for a variety of reasons, including the fact that the assumptions upon which their analysis is based lack substantiation and the fact that any possible misclassification would not have changed the conclusion of the study in question. CONCLUSION: Current evidence does not support the notion that misclassification threatens the validity of recent case-control studies investigating the relationship between CMT and VAD. Hence, the recent re-analysis cannot refute the conclusion from previous studies that CMT is not a cause of VAD.

Exploratory Analysis of Clinical Predictors of Outcomes of Nonsurgical Treatment in Patients With Lumbar Spinal Stenosis.

OBJECTIVE: The purpose of this study was to explore potential baseline physical examination and demographic predictors of clinical outcomes in patients with lumbar spinal stenosis. METHODS: This was a secondary analysis of data obtained from a pilot randomized controlled trial. Primary and secondary outcome measures were the Swiss Spinal Stenosis (SSS) Questionnaire and visual analog scale (VAS) for leg pain. Multiple regression models were used to assess 2 different outcomes: SSS at completion of care and VAS at completion of care. Separate regression models were built for each of the 2 outcomes to identify the best subset of variables that predicted improvement. Predictors with a significant contribution were retained in a final "best" model. RESULTS: Three variables were identified as having an association with SSS score at completion of care: baseline SSS score, qualitative description of leg pain, and age (adjusted R(2) = 33.2). Four variables were identified as having an association with VAS score at completion of care: baseline VAS score, qualitative description of leg pain, body mass index, and age (adjusted R(2) = 38.3). CONCLUSION: This study provides preliminary evidence supporting an association between certain baseline characteristics and nonsurgical clinical outcomes in patients with lumbar spinal stenosis.

Analysis of HCV-6 isolates among Asian-born immigrants in North America reveals their high genetic diversity and a new subtype.

We characterized full-length genomes for 15 HCV-6 isolates, all from Asian immigrants living in North America. Among these isolates, nine were novel variants showing >15% nucleotide differences from their nearest relatives, representing lineages distinct from known subtypes. The other six were classified into subtypes 6c, 6h, 6q, 6r, and 6s. The partial sequences were also determined for five additional HCV-6 isolates, three from the US and two from Canada. The latter two were assigned to new subtype 6xf as they were found to classify with two other isolates for which we recently reported their full-length genomes. We further analyzed partial Core-E1 sequences of 100 HCV-6 isolates sampled in North America, seven from the US and 93 from Canada and all from Asian immigrants except for four from Caucasians. These 100 isolates belonged to 20 assigned subtypes and 16 unclassified lineages showing great genetic diversity and enhanced significance to public health.

Vertebral artery dissection in evolution found during chiropractic examination.

A 30-year-old woman presented to an emergency department with sudden onset of transient loss of left peripheral vision. Owing to a history of migraine headaches, she was released with a diagnosis of ocular migraine. Two days later, she sought chiropractic care for the chief symptom of severe neck pain. The chiropractor suspected the possibility of vertebral artery dissection (VAD). No manipulation was performed; instead, MR angiography (MRA) of the neck was obtained, which revealed an acute left VAD with early thrombus formation. The patient was placed on aspirin therapy. Repeat MRA of the neck 3 months later revealed resolution of the thrombus, without progression to stroke. This case illustrates the importance for all healthcare providers who see patients with neck pain and headache to be attentive to the symptomatic presentation of possible VAD in progress.