The impact of expanded access to direct acting antivirals for Hepatitis C virus on patient outcomes in Canada.

Background: Hepatitis C virus (HCV) has high global prevalence and can lead to liver complications and death. Access to direct-acting antivirals (DAAs) in Canada increased following several policy changes, however the real-world impact of expanded DAA access and increased use of these drugs is unknown.

Objective: We aimed to determine the early change in rates of HCV-related hospitalizations overall and HCV-related hospitalizations with hepatocellular carcinoma (HCC) after expanded DAA access.

Association between long-term exposure to ambient air pollution and COVID-19 severity: a prospective cohort study.

Background: The tremendous global health burden related to COVID-19 means that identifying determinants of COVID-19 severity is important for prevention and intervention. We aimed to explore long-term exposure to ambient air pollution as a potential contributor to COVID-19 severity, given its known impact on the respiratory system.

Methods: We used a cohort of all people with confirmed SARS-CoV-2 infection, aged 20 years and older and not residing in a long-term care facility in Ontario, Canada, during 2020.

Vaccine Effectiveness Against SARS-CoV-2 Infection and Severe Outcomes in the Maintenance Dialysis Population in Ontario, Canada.

Background: Vaccination studies in the hemodialysis population have demonstrated decreased antibody response compared with healthy controls, but vaccine effectiveness for preventing SARS-CoV-2 infection and severe disease is undetermined.

Methods: We conducted a retrospective cohort study in the province of Ontario, Canada, between December 21, 2020, and June 30, 2021. Receipt of vaccine, SARS-CoV-2 infection, and related severe outcomes (hospitalization or death) were determined from provincial health administrative data.

Is 'conflict of interest' a Misnomer? Managing interests in immunization research and evaluation.

Potential conflicts of interest in vaccine research can lead to negative consequences that undermine public trust and thereby put communities at risk. However, collaborations that may give rise to potential conflicts between interests can also greatly facilitate appropriate, scientifically robust, and timely vaccine development, implementation, and evaluation. At present, policies regarding the management of potential conflicts between interests are not ideal.

Association of Influenza Activity and Environmental Conditions With the Risk of Invasive Pneumococcal Disease.

Importance: Streptococcus pneumoniae is the most commonly identified cause of bacterial pneumonia, and invasive pneumococcal disease (IPD) has a high case fatality rate. The wintertime coseasonality of influenza and IPD in temperate countries has suggested that pathogen-pathogen interaction or environmental conditions may contribute to IPD risk.

Objectives: To evaluate the short-term associations of influenza activity and environmental exposures with IPD risk in temperate countries and to examine the generalizability of such associations across multiple jurisdictions.

HCV-infected individuals have higher prevalence of comorbidity and multimorbidity: a retrospective cohort study.

Background: Almost 1% of Canadians are hepatitis C (HCV)-infected. The liver-specific complications of HCV are established but the extra-hepatic comorbidity, multimorbidity, and its relationship with HCV treatment, is less well known. We describe the morbidity burden for people with HCV and the relationship between multimorbidity and HCV treatment uptake and cure in the pre- and post-direct acting antiviral (DAA) era.

Methods used for immunization coverage assessment in Canada, a Canadian Immunization Research Network (CIRN) study.

Accurate and complete immunization data are necessary to assess vaccine coverage, safety and effectiveness. Across Canada, different methods and data sources are used to assess vaccine coverage, but these have not been systematically described. Our primary objective was to examine and describe the methods used to determine immunization coverage in Canada.

Admission to hospital for pneumonia and influenza attributable to 2009 pandemic A/H1N1 influenza in First Nations communities in three provinces of Canada.

Background: Early reports of the 2009 A/H1N1 influenza pandemic (pH1N1) indicated that a disproportionate burden of illness fell on First Nations reserve communities. In addition, the impact of the pandemic on different communities may have been influenced by differing provincial policies. We compared hospitalization rates for pneumonia and influenza (P&I) attributable to pH1N1 influenza between residents of First Nations reserve communities and the general population in three Canadian provinces.

Influenza and seasonal patterns of hospital use by older adults in long-term care and community settings in Ontario, Canada.

Objectives: We compared seasonal influenza hospital use among older adults in long-term care (LTC) and community settings.

Methods: We used provincial administrative data from Ontario to identify all emergency department (ED) visits and hospital admissions for pneumonia and influenza among adults older than 65 years between 2002 and 2008. We used sentinel laboratory reports to define influenza and summer seasons and estimated mean annual event rates and influenza-associated rates.

The good, bad, and ugly of online recruitment of parents for health-related focus groups: lessons learned.

Background: We describe our experiences with identifying and recruiting Ontario parents through the Internet, primarily, as well as other modes, for participation in focus groups about adding the influenza vaccine to school-based immunization programs.

Objective: Our objectives were to assess participation rates with and without incentives and software restrictions. We also plan to examine study response patterns of unique and multiple submissions and assess efficiency of each online advertising mode.

Patterns of emergency room visits, admissions and death following recommended pediatric vaccinations - a population based study of 969,519 vaccination events.

Background: The risk of immediate adverse events due to the inflammation created by a vaccine is a potential concern for pediatric vaccine programs.

Methods: We analyzed data on children born between March 2006 and March 2009 in the province of Ontario. Using the self-controlled case series design, we examined the risk of the combined endpoint of emergency room visit and hospital admission in the immediate 3 days post vaccination to a control period 9-18 days after vaccination.

Trends in influenza vaccination in Canada, 1996/1997 to 2005.

Objectives: This article reports recent trends in influenza vaccination rates in Canada, provides data on predictors of vaccination in Canada for 2005, and examines longer-term effects of Ontario's universal influenza immunization program on vaccine uptake.

Data Sources: Data are from the 1996/1997 National Population Health Survey (NPHS) and the 2000/2001, 2003, and 2005 Canadian Community Health Survey (CCHS).

Analytical Techniques: NPHS and CCHS data were used to estimate influenza vaccination rates of the population aged 12 or older.

The effect of universal influenza immunization on vaccination rates in Ontario.

Objectives: This article examines the association between introduction of Ontario's Universal Influenza Immunization Program and changes in vaccination rates over time in Ontario, compared with the other provinces combined.

Data Sources: The data are from the 1996/97 National Population Health Survey and the 2000/01 and 2003 Canadian Community Health Survey, both conducted by Statistics Canada.

Analytical Techniques: Cross-tabulations were used to estimate vaccination rates for the total population aged 12 or older, for groups especially vulnerable to the effects of influenza, and by selected socio-demographic variables.

Oral vitamin B12 therapy in the primary care setting: a qualitative and quantitative study of patient perspectives.

Background: Although oral replacement with high doses of vitamin B12 is both effective and safe for the treatment of B12 deficiency, little is known about patients' views concerning the acceptability and effectiveness of oral B12. We investigated patient perspectives on switching from injection to oral B12 therapy.

Methods: This study involved a quantitative arm using questionnaires and a qualitative arm using semi-structured interviews, both to assess patient views on injection and oral therapy.

A comparison of Canadian medical students from rural and non-rural backgrounds.

Context: Very little is known about medical students from rural areas currently enrolled in Canadian medical schools.

Purpose: We aimed to compare rural and non-rural students in terms of demographics, socioeconomic status, financial status and career choices.

Methods: As part of a larger Internet survey of all students at Canadian medical schools outside Quebec, conducted in January and February 2001, we conducted post-hoc analyses to compare students from rural and non-rural areas.

Sex differences in first-year students at Canadian medical schools.

Objectives: To compare male and female medical students by age, level of education before admission to medical school, race/ethnicity, parental education level, socioeconomic status, and attitudes toward public health care.

Methods: In 2001, we conducted an Internet-based survey of all students enrolled in the 16 medical schools across Canada. Based on the high response rate, first-year medical students at Canadian medical schools outside of Quebec were included in this analysis.

Characteristics of first-year students in Canadian medical schools.

Background: The demographic and socioeconomic profile of medical school classes has implications for where people choose to practise and whether they choose to treat certain disadvantaged groups. We aimed to describe the demographic and socioeconomic characteristics of first-year Canadian medical students and compare them with those of the Canadian population to determine whether there are groups that are over- or underrepresented. Furthermore, we wished to test the hypothesis that medical students often come from privileged socioeconomic backgrounds.

Effects of rising tuition fees on medical school class composition and financial outlook.

Background: Since 1997, tuition has more than doubled at Ontario medical schools but has remained relatively stable in other Canadian provinces. We sought to determine whether the increasing tuition fees in Ontario affected the demographic characteristics and financial outlook of medical students in that province as compared with those of medical students in the rest of Canada.

Methods: As part of a larger Internet survey of all students at Canadian medical schools outside Quebec, conducted in January and February 2001, we compared the respondents from Ontario schools with those from the other schools (control group).