OBJECTIVE: This study aims to (1) build and validate model-based case definitions for multiple sclerosis (MS) that use trends (ie, trend-based case definitions) and (2) to apply dynamic classification to identify the average number of data years needed for classification (ie, average trend needed).
METHODS: Retrospective cohort study design.
METHODS: 608 MS cases and 59 620 MS non-cases.
METHODS: Data from 1 April 2004 to 31 March 2022 were obtained from the Manitoba Population Research Data Repository. MS case status was ascertained from homecare records and linked to health data. Trend-based case definitions were constructed using multivariate generalised linear mixed models applied to annual numbers of general and specialist physician visits, hospitalisations and MS healthcare contacts or medication dispensations. Dynamic classification, which ascertains cases and non-cases annually, was used to estimate mean classification time. Classification accuracy performance measures, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), proportion correctly classified (PCC) and F1-scores, were compared for trend-based case definitions and a deterministic case definition of 3+MS healthcare contacts or medication dispensations.
RESULTS: When applied to the full study period, classification accuracy performance measure estimates for all case definitions exceeded 0.90, except sensitivity and PPV for the trend-based dynamic case definition (0.88, 0.64, respectively). PCC was high for all case definitions (0.94-0.99); F1-scores were lower for the trend-based case definitions compared with the deterministic case definition (0.74-0.93 vs 0.96). Dynamic classification identified 5 years as the average trend needed. When applied to the average trend windows, accuracy estimates for trend-based case definitions were lower than the estimates from the full study period (sensitivity: 0.77-0.89; specificity: 0.90-0.97; PPV: 0.54-0.81; NPV: 0.97-0.99; F1-score: 0.64-0.84). Accuracy estimates for the deterministic case definition remained high, except sensitivity (0.42-0.80). F1-score was variable (0.59-0.89).
CONCLUSIONS: Trend-based and deterministic case definitions classifications were similar to a population-based clinician assessment reference standard for multiple measures of classification accuracy. However, accuracy estimates for both trend-based and deterministic case definitions varied as the years of data used for classification were reduced. Dynamic classification appears to be a viable option for identifying the average trend needed for trend-based case definitions.

Syphilis, caused by Treponema pallidum subsp. pallidum (TPA), is becoming a significant public health concern, with rising incidence in Manitoba exceeding the national average. The province has also seen a demographic shift leading to women representing 51.9% of cases in 2021, leading to the re-emergence of congenital syphilis. Given the similarities in lesion appearance between TPA and other pathogens such as herpesviruses, accurate diagnosis is crucial for effective management and prevention. In order to address the potential for missed TPA cases, we conducted a quality assurance study from June 2021 to March 2023, screening over 5,000 mucocutaneous lesion swabs for TPA, initially submitted for herpes simplex virus (HSV) and varicella zoster virus (VZV) testing. Positivity rates were 13% for HSV1, 13% for HSV2, 6.7% for VZV, and 6.6% for TPA. Turnaround times (TAT) for TPA testing, as a send-out to the reference laboratory, averaged 17.8 days. Of the TPA-positive specimens, 36% did not have a corresponding TPA PCR test ordered, and 19% did not have accompanying syphilis serology within 30 days of collection. Creation of a multiplex lesion panel identified high sensitivity and specificity for HSV1, HSV2, VZV, and TPA, with robust reproducibility across multiple runs. Incorporation of TPA into a lesion panel improved the TAT to 4 days. Our findings emphasize the need for improved testing strategies to combat the syphilis epidemic and enhance public health outcomes.IMPORTANCESyphilis resurgence has become a significant global public health concern. In particular, the Canadian Prairies have been struggling with high incidence since 2016, exceeding the national Canadian average. We undertook a quality assurance study that highlighted significant gaps in diagnosis of acute syphilis, which led to the development of a highly sensitive and specific multiplex lesion assay for the dual detection of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), varicella zoster virus (VZV), and syphilis.

Bartonella are gram-negative bacilli not identified by routine bacterial culture. The objectives of this study were to review the results of all serologic testing for Bartonella ordered in Manitoba, Canada, and to review cases with positive test results among adults to assess species identification, risk factors, clinical manifestations and outcomes.
This retrospective study included all Bartonella serologic tests ordered in Manitoba and performed at the National Microbiology Laboratory, Winnipeg, from Jan. 1, 2010, until Dec. 31, 2020. We analyzed the aggregate data for all serologic tests for Bartonella for patients of all ages. We reviewed the charts of adult (age ≥ 18 yr) patients with serologic positivity for Bartonella who had a medical chart at 1 of Winnipeg\'s 2 largest hospitals (Health Sciences Centre and St. Boniface Hospital) to extract clinical and demographic data and create a case series. Descriptive statistics were performed.
During the study period, 1014 Bartonella serologic tests were ordered in adult and pediatric patients, of which 24 (2.4%) gave a positive result. Sixteen adults (12 men and 4 women; mean age 48 yr) seen at a participating hospital had a positive result. Molecular species-level identification occurred on explanted cardiac valves in 5 (31%) of the 16 cases; B. quintana was identified in all 5. Six patients (38%) were diagnosed with probable B. quintana infection, for a total of 11 B. quintana cases (69%); 8 (73%) of the 11 had endocarditis. Four cases of B. quintana infection (36%) were associated with rural residence. Four cases (25%) of probable B. henselae were identified; 2 patients had fever and lymphadenopathy, and 2 had endocarditis. The remaining patient was deemed to have a false-positive result as his B. henselae titre was at the threshold for positivity, his B. quintana serologic test gave a negative result, and his clinical syndrome was not suggestive of Bartonella infection. Two patients died; both had multivalvular B. quintana endocarditis with ruptured intracranial mycotic aneurysms.
Bartonella quintana was a common cause of Bartonella serologic positivity among adults in Manitoba in 2010-2020 and was associated with endocarditis and systemic embolization. As B. quintana is transmitted by body lice, active case finding for people who lack suitable housing, both in urban and rural settings, should prioritize those with elevated Bartonella titres to receive echocardiography and detect endocarditis before systemic embolization occurs.

Understanding care patterns of persons living with HIV prior to diagnosis can inform prevention opportunities, earlier diagnosis, and engagement strategies. We examined healthcare utilization among HIV-positive individuals and compared them to HIV-negative controls.
Data were from a retrospective cohort from Manitoba, Canada. Participants included individuals living with HIV presenting to care between 2007 and 2011, and HIV-negative controls, matched (1:5) by age, sex, and region. Data from population-based administrative databases included physician visits, hospitalizations, drug dispensation, and chlamydia and gonorrhea testing. Diagnoses associated with physician visits were classified according to International Classification of Diseases chapters. Conditional logistic regression models were used to compare cases/controls, with adjusted odds ratios (AORs) and their 95% confidence intervals (95% CI) reported.
A total of 193 cases and 965 controls were included. Physician visits and hospitalizations were higher for cases, compared to controls. In the 2 years prior to case date, cases were more likely to be diagnosed with \"blood disorders\" (AOR: 4.2, 95% CI: 2.0-9.0), be treated for mood disorders (AOR: 2.4, 95% CI: 1.6-3.4), and to have 1+ visits to a hospital (AOR: 2.2, 95% CI: 1.4-3.6).
Opportunities exist for prevention, screening, and earlier diagnosis. There is a need for better integration of healthcare services with public health.

Despite scientific evidence that climate change has profound and far reaching implications for public health, translating this knowledge in a manner that supports citizen engagement, applied decision-making, and behavioural change can be challenging. This is especially true for complex vector-borne zoonotic diseases such as Lyme disease, a tick-borne disease which is increasing in range and impact across Canada and internationally in large part due to climate change. This exploratory research aims to better understand public risk perceptions of climate change and Lyme disease in order to increase engagement and motivate behavioural change.
A focus group study involving 61 participants was conducted in three communities in the Canadian Prairie province of Manitoba in 2019. Focus groups were segmented by urban, rural, and urban-rural geographies, and between participants with high and low levels of self-reported concern regarding climate change.
Findings indicate a broad range of knowledge and risk perceptions on both climate change and Lyme disease, which seem to reflect the controversy and complexity of both issues in the larger public discourse. Participants in high climate concern groups were found to have greater climate change knowledge, higher perception of risk, and less skepticism than those in low concern groups. Participants outside of the urban centre were found to have more familiarity with ticks, Lyme disease, and preventative behaviours, identifying differential sources of resilience and vulnerability. Risk perceptions of climate change and Lyme disease were found to vary independently rather than correlate, meaning that high climate change risk perception did not necessarily indicate high Lyme disease risk perception and vice versa.
This research contributes to the growing literature framing climate change as a public health issue, and suggests that in certain cases climate and health messages might be framed in a way that strategically decouples the issue when addressing climate skeptical audiences. A model showing the potential relationship between Lyme disease and climate change perceptions is proposed, and implications for engagement on climate change health impacts are discussed.

Manitoba-oculo-tricho-anal (MOTA) syndrome is a rare syndrome with only 27 cases reported worldwide so far, but none was reported in the population of Eastern Asia. Such extremely low prevalence might be contributed by misdiagnosis due to its similarities in ocular manifestations with facial cleft. In our study, we discovered the first case of MOTA syndrome in the population of China, with 2 novel FRAS1 related extracellular matrix 1 (FREM1) gene stop-gain mutations confirmed by whole exome sequencing.
A 12-year-old Chinese girl presented with facial cleft-like deformities including aberrant hairline, blepharon-coloboma and broad bifid nose since birth. Whole exome sequencing resulted in the identification of 2 novel stop-gain mutations in the FREM1 gene. Diagnosis of MOTA syndrome was then established.
We discovered the first sporadic case of MOTA syndrome according to clinical manifestations and genetic etiology in the Chinese population. We have identified 2 novel stop-gain mutations in FREM1 gene which further expands the spectrum of mutational seen in the MOTA syndrome. Further research should be conducted for better understanding of its mechanism, establishment of an accurate diagnosis, and eventually the exploitation of a more effective and comprehensive therapeutic intervention for MOTA syndrome.

Increasing intensification in swine production has led to new and specialized technologies, but the occupational health and safety impacts are rarely quantified in the business plans for adoption. Needle-less injection has potential to increase productivity and eliminate needle stick injury in workers, but it is not clear whether these benefits offset high capital investment and potential increases in musculoskeletal loads. This economic evaluation employed probabilistic scenario analysis using injury, cost, and production data gathered from interviews with swine producers in Manitoba and Saskatchewan. After adoption of needle-less injection, rates of needle-stick injury went down with no measureable effect on upper limb musculoskeletal disorders, resulting in lower health and safety costs for needle-less injectors. Needle-less injection duration was 40% faster once workers acclimatized, but large start-up costs mean economic benefits are realized only after the first year. The incremental benefit cost ratio promoted adoption of needle-less injectors over conventional needles for the base case of a 1200 sow barn; the conventional method is beneficial for barns with 600 sows or less. Findings indicate that well-designed technologies have the potential to achieve the dual ergonomics goals of enhancing human wellbeing and system performance. We anticipate that the economic and decision models developed in this study can be applied to other new technologies in agriculture and animal production.

Social determinants of health (SDoH) influence risk of injury. We conducted a population-based, case-control study to identify which social determinants influence burn injury in children. Children (≤16 years of age) admitted to a Canadian regional burn center between January 1, 1999 and March 30, 2017 were matched based on age, sex, and geographic location 1:5 with an uninjured control cohort from the general population. Population-level administrative data describing the SDoH at the Manitoba Center for Health Policy (MCHP) were compared between the cohorts. Specific SDoH were chosen based on a published systematic review conducted by the research team. In the final multivariable model, children from a low-income household odds ratio (OR) (95% confidence interval) 1.97 (1.46, 2.65), in care 1.57 (1.11, 2.21), from a family that received income assistance 1.71 (1.33, 2.19) and born to a teen mother 1.43 (1.13, 1.81) were significantly associated with an increased risk of pediatric burn injury. This study identified SDoH that are associated with an increased risk of burn injury. This case-control study supports the finding that children from a low-income household, children in care, from a family that received income assistance, and children born to a teen mother are at an elevated risk of burn injury. Identifying children at increased potential risk allows targeting of burn risk reduction and home safety programs.

In children with epilepsy, fever and illness are known triggers for seizure; therefore, clinicians and parents could be concerned that immunization-induced inflammation and fever could also trigger seizures. We sought to estimate the risk of emergency department (ED) visit or hospitalization for epilepsy/seizure and all causes after immunization in children younger than 7 years of age with epilepsy.
We conducted a self-controlled case series of children diagnosed with epilepsy before their 7th birthday and immunized from 2005 to 2015 in Ontario (population 14.2 million) and Manitoba (population 1.3 million), Canada, using administrative healthcare data. We estimated the age- and season-adjusted relative incidence (aRI) of epilepsy/seizure-related and all-cause ED visits/hospitalizations during various risk periods 0-28 days after inactivated and live immunizations versus a control period 35-83 days postimmunization. Estimates from each province were analyzed separately and then combined in a random-effects meta-analysis.
The combined risk of epilepsy/seizure-related hospitalization/ED visit was increased 0-2 days after inactivated vaccines (aRI = 1.5, 95% confidence interval: 1.1-1.9) and 7-10 days after live vaccines (aRI = 1.9, 1.4-2.7). For all-cause ED visit/hospitalization, the combined aRI estimate was 0.9 (0.8-1.2) 0-2 days after inactivated vaccines and 1.3 (1.1-1.5) 7-10 days after live vaccines.
The risk of epilepsy/seizure-related ED visit/hospitalization was modestly increased among children with epilepsy during peak periods of fever and inflammation following inactivated and live vaccines. These risks must be balanced against the risk of complications from vaccine-preventable diseases.

Administrative data is increasingly used for chronic disease surveillance; however, its validity to define cases of chronic kidney disease (CKD) in children is unknown. We sought to evaluate the performance of case definitions for CKD in children.
We utilized population-based administrative data from the Manitoba Center for Health Policy to evaluate the validity of algorithms based on a combination of hospital claims, outpatient physician visits, and pharmaceutical use over 1-3 years in children <18 years of age. Algorithms were compared with a laboratory-based definition (estimated glomerular filtration rate < 90 ml/min/1.73 m2 and/or presence of proteinuria).
All algorithms evaluated had very low sensitivity (0.20-0.39) and moderate positive predictive value (0.52-0.68). Algorithms had excellent specificity (0.98-0.99) and negative predictive value (0.96-0.97). Receiver operating characteristic (ROC) curves indicate fair accuracy (0.60-0.68). Sensitivity improved with increasing years of data. One or more physician claims and one or more prescriptions over 3 years had the highest sensitivity and ROC.
The sensitivity of administrative data algorithms for CKD is unacceptably low for a screening test. Specificity is excellent; therefore, children without CKD are correctly identified. Alternate data sources are required for population-based surveillance of this important chronic disease.