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Background In British Columbia, Canada, most adults 50–69 years old became eligible for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine in April 2021, with chimpanzee adenoviral vectored vaccine (ChAdOx1) restricted to ≥55-year-olds and second doses deferred ≥6 weeks to optimize single-dose coverage. Methods Among adults 50–69 years old, single-dose messenger RNA (mRNA) and ChAdOx1 vaccine effectiveness (VE) against SARS-CoV-2 infection and hospitalization, including variant-specific, was assessed by test-negative design between 4 April and 2 October 2021. Results Single-dose VE included 11 861 cases and 99 544 controls. Median of postvaccination follow-up was 32 days (interquartile range, 15–52 days). Alpha, Gamma, and Delta variants comprised 23%, 18%, and 56%, respectively, of genetically characterized viruses. At 21–55 days postvaccination, single-dose mRNA and ChAdOx1 VE (95% confidence interval [CI]) was 74% (71%–76%) and 59% (53%–65%) against any infection and 86% (80%–90%) and 94% (85%–97%) against hospitalization, respectively. VE (95% CI) was similar against Alpha and Gamma infections for mRNA (80% [76%–84%] and 80% [75%–84%], respectively) and ChAdOx1 (69% [60%–76%] and 66% [56%–73%], respectively). mRNA VE was lower at 63% (95% CI, 56%–69%) against Delta but 85% (95% CI, 71%–92%) against Delta-associated hospitalization (nonestimable for ChAdOx1). Conclusions A single mRNA or ChAdOx1 vaccine dose gave important protection against SARS-CoV-2, including early variants of concern. ChAdOx1 VE was lower against infection, but 1 dose of either vaccine reduced the hospitalization risk by >85% to at least 8 weeks postvaccination. Findings inform program options, including longer dosing intervals.

Recent evidence from the United States and Canada suggests an unexplained increase in small-for-gestational-age (SGA) births (10th percentile). This study aimed to identify reasons for the recent increase in SGA births in Canada.Using Canada's Vital Statistics - Birth Database, the study population included all singleton live births, 2000 to 2016, inclusive. Temporal changes in birth weight (grams), birth weight for gestational age z-scores, and SGA births were examined. Multivariable logistic regression was used to determine if the ncreased risk of an SGA birth over time was eliminated or attenuated by adjusting for selected individual and sociodemographic factors that have previously been associated with SGA births.There were 5,941,820 singleton live births in Canada between 2000 and 2016. Mean birth weight for all births decreased from 3,442 grams in 2000, to 3,367 grams in 2016, while SGA birth increased from 7.2% in 2000 to 8.0% in 2016. The multivariable model showed higher odds of SGA birth among births to parents born outside of Canada, unmarried women, older women, nulliparous women and women residing in low income neighborhoods. After adjusting for sociodemographic factors, the crude 12% increase in odds of SGA birth in 2016 compared to 2000 (95% Confidence Interval (CI): [10 to 14%]) was attenuated, ut not eliminated (adjusted odds ratio for calendar time 1.08 (95% CI: [1.06, 1.10])).This study identified a decrease in fetal size in Canada between 2000 and 2016. The rise in SGA births in Canada was explained only partly as a result of concurrent changes in the demography of childbirth.

Background One- and two-dose mRNA vaccine effectiveness (VE) estimates against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by dosing interval and time since vaccination were assessed among healthcare workers (HCWs) in publicly funded acute and community (nonresidential) healthcare facilities in British Columbia, Canada. Methods A test-negative design was used with controls matched to cases (6:1) on epidemiological week of SARS-CoV-2 test date. mRNA vaccination was defined by receipt of the first dose ≥21 days or second dose ≥14 days before the test date. HCWs ≥18 years old tested for SARS-CoV-2 between epi-weeks 3 and 39 (January 17–October 2, 2021) were included, when varying dosing intervals and a mix of circulating variants of concern contributed, including Delta dominance provincially from epi-week 31 (August 1). Results Single- and two-dose analyses included 1265 and 1246 cases, respectively. The median follow-up period (interquartile range) was 49 (34–69) days for single-dose and 89 (61–123) days for two-dose recipients, with 12%, 31%, and 58% of second doses given 3–5, 6, or ≥7 weeks after the first. Adjusted mRNA VE against SARS-CoV-2 was 71% (95% CI, 66%–76%) for one dose and 90% (95% CI, 88%–92%) for two doses, similar to two heterologous mRNA doses (92%; 95% CI, 86%–95%). Two-dose VE remained >80% at ≥28 weeks post–second dose. Two-dose VE was consistently 5%–7% higher with a ≥7-week vs 3–5-week interval between doses, but with overlapping confidence intervals. Conclusions Among HCWs, we report substantial single-dose and strong and sustained two-dose mRNA vaccine protection, with the latter maintained for at least 7 months. These findings support a longer interval between doses, with global health and equity implications.

Background The Canadian coronavirus disease 2019 (COVID-19) immunization strategy deferred second doses and allowed mixed schedules. We compared 2-dose vaccine effectiveness (VE) by vaccine type (mRNA and/or ChAdOx1), interval between doses, and time since second dose in 2 of Canada’s larger provinces. Methods Two-dose VE against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or hospitalization among adults ≥18 years, including due to Alpha, Gamma, and Delta variants of concern (VOCs), was assessed ≥14 days postvaccination by test-negative design studies separately conducted in British Columbia and Quebec, Canada, between 30 May and 27 November (epi-weeks 22–47) 2021. Results In both provinces, all homologous or heterologous mRNA and/or ChAdOx1 2-dose schedules were associated with ≥90% reduction in SARS-CoV-2 hospitalization risk for ≥7 months. With slight decline from a peak of >90%, VE against infection was ≥80% for ≥6 months following homologous mRNA vaccination, lower by ∼10% when both doses were ChAdOx1 but comparably high following heterologous ChAdOx1 + mRNA receipt. Findings were similar by age group, sex, and VOC. VE was significantly higher with longer 7–8-week versus manufacturer-specified 3–4-week intervals between mRNA doses. Conclusions Two doses of any mRNA and/or ChAdOx1 combination gave substantial and sustained protection against SARS-CoV-2 hospitalization, spanning Delta-dominant circulation. ChAdOx1 VE against infection was improved by heterologous mRNA series completion. A 7–8-week interval between first and second doses improved mRNA VE and may be the optimal schedule outside periods of intense epidemic surge. Findings support interchangeability and extended intervals between SARS-CoV-2 vaccine doses, with potential global implications for low-coverage areas and, going forward, for children.

IntroductionIn randomized controlled trials, single-dose efficacy against SARS-CoV-2 illness exceeded 90% for mRNA vaccines (BNT162b2 and mRNA-1273), and 75% for ChAdOx1. In British Columbia (BC), Canada second doses were deferred up to 16 weeks and ChAdOx1 was only initially recommended for adults 55 years of age and older. We compared single-dose vaccine effectiveness (VE) during the spring 2021 wave in BC when Alpha and Gamma variants of concern (VOC) predominated.MethodsVE was estimated against infection and hospitalization by test-negative design: cases were RT-PCR test-positive for SARS-CoV-2 and controls were test-negative. Adults 50-69 years old with specimen collection between April 4 and May 22 (weeks 14-20) were included. Variant-specific VE was estimated between weeks 17-20 when genetic characterization of all case viruses was performed, primarily through whole genome sequencing.ResultsVE analyses included 7,116 (10%) cases and 60,958 controls. Three-quarters of vaccinated participants received mRNA vaccine (60% BNT162b2, 15% mRNA-1273) and 25% received ChAdOx1. Half of genetically characterized viruses were Alpha, with 38% Gamma, 4% Delta and 8% non-VOCs. Single-dose VE against any infection was 75% (95%CI: 72-78) for BNT162b2, 82% (95%CI: 76-87) for mRNA-1273 and 61% (95%CI: 54-66) for ChAdOx1. VE against hospitalization was 83% (95%CI: 76-89), 85% (95%CI: 63-94) and 96% (95%CI: 86-99), respectively. VE against Alpha vs. Gamma infections did not differ among mRNA (78%;95%CI: 73-82 and 80%;95%CI: 74-85) or ChAdOx1 (66%;95%CI: 57-74 and 60%;95%CI: 48-69) recipients.ConclusionsA single dose of mRNA vaccine reduced the SARS-CoV-2 infection risk by at least 75%, including infections due to early VOC. Although effectiveness of a single dose of ChAdOx1 was lower at 60% against infection, just one dose of any vaccine reduced the hospitalization risk by more than 80%. In the context of constrained vaccine supplies, these findings have implications for global vaccine deployment to reduce the overall burden of infections and hospitalizations due to SARS-CoV-2.

IntroductionWhile the socioeconomic impact of a cancer diagnosis on cancer survivors has gained some attention in the literature, to our knowledge, a review of the evidence on changes in income due to cancer has yet to be undertaken. In this paper, we describe a scoping review protocol to review the evidence on the effect of a cancer diagnosis on the income of individuals diagnosed with cancer during adulthood (≥18 years). The purpose is to summarise existing evidence, identify gaps in current research and highlight priority areas for future research.Methods and analysisThis study will follow the methodological framework for conducting scoping reviews by the Joanna Briggs Institute In collaboration with a health science librarian, we developed a search strategy to be performed in Ovid MEDLINE, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, EMBASE, Econ-Literature and Evidence-Based Medicine Reviews. This scoping review will search the scientific literature published in English from 1 January 2000 to 31 December 2020. Studies that measured the impact of cancer on income of adults will be eligible for inclusion. Studies exclusively focused on employment outcomes (eg, return to work, unemployment, productivity loss), financial expenditures, childhood cancer survivors and/or the caregivers of cancer survivors will be excluded. Three independent reviewers will conduct screening and extract data. Descriptive information will be reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews.Ethics and disseminationThis scoping review will analyse data from publicly available materials and thus does not require ethics approval. Results from this review will be disseminated through a peer-reviewed publication and/or conference presentation with the potential to identify gaps in the literature, suggest strategies for standardised terminology and provide directions for future research.

IntroductionRandomized-controlled trials of mRNA vaccine protection against SARS-CoV-2 included relatively few elderly participants. We assess singe-dose mRNA vaccine effectiveness (VE) in adults ≥70-years-old in British Columbia (BC), Canada where the second dose was deferred by up to 16 weeks and where a spring 2021 wave uniquely included co-dominant circulation of B.1.1.7 and P.1 variants of concern (VOC).MethodsAnalyses included community-dwelling adults ≥70-years-old with specimen collection between April 4 (epidemiological week 14) and May 1 (week 17). Adjusted VE was estimated by test-negative design through provincial laboratory and immunization data linkage. Cases were RT-PCR test-positive for SARS-CoV-2 and controls were test-negative. Vaccine status was defined by receipt of a single-dose ≥21 days before specimen collection, but a range of intervals was assessed. In variant-specific analyses, test-positive cases were restricted to those genetically-characterized as B.1.1.7, P.1 or non-VOC.ResultsVE analyses included 16,993 specimens: 1,226 (7.2%) test-positive cases and 15,767 test-negative controls. Of 1,131 (92%) viruses genetically categorized, 509 (45%), 314 (28%) and 276 (24%) were B.1.1.7, P.1 and non-VOC lineages, respectively. VE was negligible at 14% (95% CI 0-26) during the period 0-13 days post-vaccination but increased from 43% (95% CI 30-53) at 14-20 days to 75% (95% CI 63-83) at 35-41 days post-vaccination. VE at ≥21 days was 65% (95% CI 58-71) overall: 72% (95% CI 58-81), 67% (95% CI 57-75) and 61% (95% CI 45-72) for non-VOC, B.1.1.7 and P.1, respectively.ConclusionsA single dose of mRNA vaccine reduced the risk of SARS-CoV-2 in adults ≥70-years-old by about two-thirds, with protection only minimally reduced against B.1.1.7 and P.1 variants. Substantial single-dose protection in older adults reinforces the option to defer the second dose when vaccine supply is scarce and broader first-dose coverage is needed.

Background Randomized-controlled trials of messenger RNA (mRNA) vaccine protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) included relatively few elderly participants. We assess single-dose mRNA vaccine effectiveness (VE) in adults ≥ 70 years old in British Columbia, Canada, where second doses were deferred by up to 16 weeks and where a spring 2021 wave uniquely included codominant circulation of Alpha (B.1.1.7) and Gamma (P.1) variants of concern (VOC). Methods Analyses included community-dwelling adults ≥ 70 years old with specimen collection between 4 April (epidemiological week 14) and 1 May (week 17) 2021. Adjusted VE was estimated by test-negative design. Cases were reverse-transcription polymerase chain reaction (RT-PCR) test-positive for SARS-CoV-2, and controls were test-negative. Vaccine status was defined by receipt of a single-dose ≥ 21 days before specimen collection, but a range of intervals was assessed. Variant-specific VE was estimated against viruses genetically characterized as Alpha, Gamma or non-VOC lineages. Results VE analyses included 16 993 specimens: 1226 (7%) test-positive cases and 15 767 test-negative controls. Of 1131 (92%) genetically characterized viruses, 509 (45%), 314 (28%), and 276 (24%) were Alpha, Gamma, and non-VOC lineages, respectively. At 0–13 days postvaccination, VE was negligible at 14% (95% confidence interval [CI], 0–26) but increased from 43% (95% CI, 30–53) at 14–20 days to 75% (95% CI, 63–83) at 35–41 days postvaccination. VE at ≥ 21 days postvaccination was 65% (95% CI, 58–71) overall: 72% (95% CI, 58–81), 67% (95% CI, 57–75), and 61% (95% CI, 45–72) for non-VOC, Alpha, and Gamma variants, respectively. Conclusions A single dose of mRNA vaccine reduced the risk of SARS-CoV-2 by about two-thirds in adults ≥ 70 years old, with protection only minimally reduced against Alpha and Gamma variants., Vaccine effectiveness estimated by test-negative design in British Columbia, Canada, shows one dose of mRNA vaccine reduced the risk of SARS-CoV-2 infection in adults ≥70-years-old by about two-thirds, with protection only minimally reduced against Alpha (B.1.1.7) and Gamma (P.1) variants.

Objectives Delayed discharge, remaining in acute care longer than medically necessary, reflects less than optimal use of hospital care resources and can have negative implications for patients. We studied (1) the change over time in delayed discharge in people with and without dementia, and (2) the association of delayed discharge with discharge destination and with the continuity of primary care prior to urgent admission. Design A retrospective population-based study. Setting and Participants Delayed discharge after urgent admission and length of delayed discharge were studied in all hospital users aged ≥70 years with at least 1 urgent admission in British Columbia, Canada, in years 2001/02, 2005/06, 2010/11, and 2015/16 (N = 276,299). Methods Linked administrative data provided by Population Data BC were analyzed using generalized estimating equations (GEE), logistic regression analysis, and negative binomial regression analyses. Results Delayed discharge increased among people with dementia and decreased among people without dementia, whereas the length of delay decreased among both. Dementia was the strongest predictor of delayed discharge [odds ratio 4.76; 95% confidence interval (CI) 4.59–4.93], whereas waiting for long-term care placement [incidence rate ratio (IRR) 1.56; 95% CI 1.50–1.62] and dementia (IRR 1.50; 95% CI 1.45–1.54) predicted a higher number of days of delay. Continuity and quantity of care with the same physician before urgent admission was associated with a decreased risk of delayed discharge, especially in people with dementia. Conclusions and Implications This study demonstrates the need for better system integration and patient-centered care especially for people with dementia. Population aging will likely increase the number of patients at risk of delayed discharge. Delayed discharge is associated with both the patient's complex needs and the inability of the system to meet these needs during and after urgent care. Sufficient investments are needed in both primary care and long-term care resources to reduce delayed discharges.

Delayed hospital discharge, also known as alternate level of care (ALC) in Canada, refers to a stay in hospital when acute services are no longer needed but the patient occupies a hospital bed while waiting to be discharged to an appropriate care setting. ALC has negative consequences for both the service system (high costs, inappropriate use of hospital resources) and individuals (feelings of uncertainty, functional loss). Extensive administrative health care data from British Columbia, Canada, were employed to study differences in ALC between people with and without dementia in 2001/02, 2005/06, 2010/11 and 2015/16, and whether continuity in physician–patient relationships prior to hospitalization is associated with ALC. We analyzed designation of ALC and length of stay in ALC, using generalized estimating equations logistic regression and negative binomial regression analysis. Of all individual, residential area and health care related factors, dementia was the single most important factor increasing the odds of designation of ALC (OR 4.76, 95%CI 4.59, 4.93). Dementia also added to the length of stay in ALC. Proportion of patients designated to ALC increased over the study years. Higher number of visits to the same general practitioner (GP) prior to hospitalization decreased the odds of ALC, especially in people with dementia. As populations age, the number of people with dementia is increasing. Efforts to control ALC have resulted in greater concentration of ALC among people with dementia. Higher continuity GP care may be a way to help understand and control these trends.