Risk of SARS-CoV-2 infection in a large cohort of Ontario workers

IntroductionWork is a key determinant of COVID-19 outcomes, however occupational surveillance is a critical information gap in many countries, including Canada. Understanding the risk of SARS-CoV-2 by occupation can identify high risk groups that can be targeted for prevention strategies.Materials and MethodsThe cohort includes 1,205,847 former workers compensation (non-COVID-19) claimants (aged 15–65) linked to health databases in Ontario, Canada. Incident cases were defined as either having a confirmed positive polymerase chain reaction (PCR) test in the Ontario Laboratory Information System (OLIS), or an International Classification of Diseases (ICD-10-CA) diagnostic code of U07.1 in hospitalization or emergency department records (February 2020-December 2021). Workers were followed until diagnosis, death, emigration, age 65 or end of follow-up. Sex- and age-adjusted Cox proportional hazards models were used to estimate hazards ratios (HR) and 95% confidence intervals (CI) by occupation, compared to all other cohort members. Analyses were also conducted to examine occupational trends in testing and diagnosis during waves of infection.ResultsOverall, 80,740 COVID-19 cases were diagnosed among workers during follow-up, of those, 80% were diagnosed with a positive PCR test. Associations were identified between COVID-19 diagnosis and employment in nursing (HR=1.44, CI95%=1.40–1.49), air transport operating (HR=1.61, CI95%=1.47–1.77), textile/fur/leather products fabricating, assembling, and repairing (HR=1.38, CI95%=1.25–1.54), apparel and furnishing services (HR=1.38, CI95%=1.19–1.60), and janitor and cleaning services (HR=1.11, CI95%=1.06–1.16). Restricted analyses where health care workers were omitted from the comparison group strengthened some associations for other high-risk workers. Test positivity ranged between 4–16% across major occupation groups. Risks varied over time and with changes in protective measures in workplaces and in broader communities.ConclusionsElevated risk of SARS-CoV-2 infection in health care, manufacturing, transportation, and service workers were identified, underscoring the importance of including occupational data in COVID-19 surveillance. Occupational trends in severe outcomes and vaccination are also being explored.

Income precarity and child and parent weight change during the COVID-19 pandemic: a cross-sectional analysis of the Ontario Parent Survey.

OBJECTIVES: To describe child and parent weight change during the pandemic, overall and by income precarity. DESIGN: A cross-sectional online survey was conducted. SETTING: Caregivers of children 0-17 years of age living in Ontario, Canada, during the COVID-19 pandemic from May 2021 to July 2021. PARTICIPANTS: A convenience sample of parents (n=9099) with children (n=9667) living in Ontario were identified through crowdsourcing. PRIMARY OUTCOME MEASURE: Parents recalled, for themselves and their child, whether they lost weight, gained weight or remained the same over the past year. OR and 95% CI were estimated using multinomial logistic regression for the association between income precarity variables and weight loss or gain, adjusted for age, gender and ethnicity. RESULTS: Overall, 5.5% of children lost weight and 20.2% gained weight. Among adolescents, 11.1% lost weight and 27.1% gained weight. For parents, 17.1% reported weight loss and 57.7% reported weight gain. Parent weight change was strongly associated with child weight change. Income precarity measures, including job loss by both parents (OR=7.81, 95% CI 5.16 to 11.83) and disruption to household food supply (OR=6.05, 95% CI 4.77 to 7.68), were strongly associated with child weight loss. Similarly, job loss by both parents (OR=2.03, 95% CI 1.37 to 3.03) and disruption to household food supply (OR=2.99, 95% CI 2.52 to 3.54) were associated with child weight gain. CONCLUSIONS: Weight changes during the COVID-19 pandemic were widespread and income precarity was strongly associated with weight loss and weight gain in children and parents. Further research is needed to investigate the health outcomes related to weight change during the pandemic, especially for youth, and the impacts of income precarity.

Neighbourhood-level socio-demographic characteristics and risk of COVID-19 incidence and mortality in Ontario, Canada: A population-based study.

OBJECTIVES: We aimed to estimate associations between COVID-19 incidence and mortality with neighbourhood-level immigration, race, housing, and socio-economic characteristics. METHODS: We conducted a population-based study of 28,808 COVID-19 cases in the provincial reportable infectious disease surveillance systems (Public Health Case and Contact Management System) which includes all known COVID-19 infections and deaths from Ontario, Canada reported between January 23, 2020 and July 28, 2020. Residents of congregate settings, Indigenous communities living on reserves or small neighbourhoods with populations <1,000 were excluded. Comparing neighbourhoods in the 90th to the 10th percentiles of socio-demographic characteristics, we estimated the associations between 18 neighbourhood-level measures of immigration, race, housing and socio-economic characteristics and COVID-19 incidence and mortality using Poisson generalized linear mixed models. RESULTS: Neighbourhoods with the highest proportion of immigrants (relative risk (RR): 4.0, 95%CI:3.5-4.5) and visible minority residents (RR: 3.3, 95%CI:2.9-3.7) showed the strongest association with COVID-19 incidence in adjusted models. Among individual race groups, COVID-19 incidence was highest among neighbourhoods with the high proportions of Black (RR: 2.4, 95%CI:2.2-2.6), South Asian (RR: 1.9, 95%CI:1.8-2.1), Latin American (RR: 1.8, 95%CI:1.6-2.0) and Middle Eastern (RR: 1.2, 95%CI:1.1-1.3) residents. Neighbourhoods with the highest average household size (RR: 1.9, 95%CI:1.7-2.1), proportion of multigenerational families (RR: 1.8, 95%CI:1.7-2.0) and unsuitably crowded housing (RR: 2.1, 95%CI:2.0-2.3) were associated with COVID-19 incidence. Neighbourhoods with the highest proportion of residents with less than high school education (RR: 1.6, 95%CI:1.4-1.8), low income (RR: 1.4, 95%CI:1.2-1.5) and unaffordable housing (RR: 1.6, 95%CI:1.4-1.8) were associated with COVID-19 incidence. Similar inequities were observed across neighbourhood-level sociodemographic characteristics and COVID-19 mortality. CONCLUSIONS: Neighbourhood-level inequities in COVID-19 incidence and mortality were observed in Ontario, with excess burden experienced in neighbourhoods with a higher proportion of immigrants, racialized populations, large households and low socio-economic status.

Changes in chronic disease risk factors and current exercise habits among Canadian adults living with and without a child during the COVID-19 pandemic.

Background: Canadians have been gravely impacted by the COVID-19 pandemic, and adults living with children may have been disproportionately impacted. The objective of this study was to describe changes in chronic disease risk factors and current exercise habits among adults living with and without a child younger than 18 years old. Data and Methods: A repeated cross-sectional study was conducted using data collected from Canadians aged 15 and older via the Canadian Perspective Survey Series (CPSS) in late March (CPSS1, N=4,383), early May (CPSS2, N=4,367) and mid-July 2020 (CPSS4, N=4,050). This analysis included participants aged 25 and older. At three points during 2020, participants reported whether they increased, decreased, or had not changed their consumption of alcohol, tobacco and junk food or sweets, their screen use, and whether they currently exercised indoors or outdoors. Behaviours were compared for adults living with and without a child, and unadjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression. Results: The presence of a child in the household was associated with higher odds of increased (compared with decreased or no change) alcohol consumption at all three time points, consumption of junk food and sweets at CPSS1 (OR: 1.69, 95% CI: 1.09-2.60), and time on the Internet at CPSS1 (OR: 1.59, 95% CI: 1.05-2.41) and CPSS4 (OR: 1.56, 95% CI: 1.05-2.29). Compared with older adults (aged 55 and older), younger adults (aged 25 to 54) were more likely to exhibit increases in chronic disease risk factors regardless of the presence of a child in the household. Interpretation: A substantial proportion of Canadian adults reported increased chronic disease risk factors during the pandemic, with greater increases noted among adults living with a child, compared with those living without a child. Public health interventions are urgently needed to mitigate the long-term impact of the pandemic on population health.

Interrupted time series analysis of Canadian legal cannabis sales during the COVID-19 pandemic.

INTRODUCTION: There were repeated reports of increased cannabis sales, use and health impacts in Canada during the COVID-19 pandemic. However, it was unclear whether the increases were due to pandemic effects or industry expansion. METHODS: We performed interrupted time series regressions of monthly per capita legal cannabis sales from March 2019 to February 2021, first with national averages, then with provincial/territorial data after adjusting for store density. We considered two interruption alternatives: January 2020, when product variety increased; and March 2020, when pandemic restrictions began. RESULTS: The provincial/territorial regression with the January interruption explained R2  = 69.6% of within-jurisdiction variation: baseline monthly per capita sales growth averaged $0.21 (95% confidence interval [CI] 0.15, 0.26), sales immediately dropped in January by $1.02 (95% CI -1.67, -0.37), and monthly growth thereafter increased by $0.16 (95% CI 0.06, 0.25). With the March interruption, the regression instead explained 68.7% of variation: baseline sales growth averaged $0.14 (95% CI 0.06, 0.22), there was no immediate drop and growth thereafter increased by $0.22 per month (95% CI 0.08, 0.35). DISCUSSION AND CONCLUSIONS: Increasing cannabis sales during the pandemic was consistent with pre-existing trends and increasing store numbers. The extra increased growth was more aligned with January's new product arrivals than with March's pandemic measures, though the latter cannot be ruled out. We found little evidence of pandemic impacts on Canada's aggregate legal cannabis sales. We therefore caution against attributing increased population-level cannabis use or health impacts primarily to the pandemic.

Incidence of outbreak-associated COVID-19 cases by industry in Ontario, Canada, 1 April 2020-31 March 2021.

OBJECTIVES: The objective of our study was to estimate the rate of workplace outbreak-associated cases of COVID-19 by industry in labour market participants aged 15-69 years who reported working the majority of hours outside the home in Ontario, Canada. METHODS: We conducted a population-based cross-sectional study of COVID-19 workplace outbreaks and associated cases reported in Ontario between 1 April 2020 and 31 March 2021. All outbreaks were manually classified into two-digit North American Industry Classification System codes. We obtained monthly denominator estimates from the Statistics Canada Labour Force Survey to estimate the incidence of outbreak-associated cases per 100 000 000 hours among individuals who reported the majority of hours were worked outside the home. We performed this analysis across industries and in three distinct time periods. RESULTS: Overall, 12% of cases were attributed to workplace outbreaks among working-age adults across our study period. While incidence varied across the time periods, the five industries with the highest incidence rates across our study period were agriculture, healthcare and social assistance, food manufacturing, educational services, and transportation and warehousing. CONCLUSIONS: Certain industries have consistently increased the incidence of COVID-19 over the course of the pandemic. These results may assist in ongoing efforts to reduce transmission of COVID-19 by prioritising resources, as well as industry-specific guidance, vaccination and public health messaging.

Changes in the dollar value of per capita alcohol, essential, and non-essential retail sales in Canada during COVID-19.

BACKGROUND: Multiple survey reports suggest that alcohol use has increased in Canada during the COVID-19 pandemic. However, less is known about how per capita alcohol sales, which predict population-level alcohol use, have changed and whether changes in alcohol sales differ from changes in sales of other products due to pandemic factors. METHODS: We obtained monthly retail sales data by industry from Statistics Canada, for the six largest provinces in Canada (containing 93% of the national population), between January 2010 and November 2020, representing time before and 9 months after the start of the pandemic in Canada. We used an interrupted time series analysis to estimate pandemic impacts on the dollar value of monthly per capita (per individuals 15+ years) alcohol, essential and non-essential retail sales. We adjusted our analyses for pre-pandemic sales trends, inflation, seasonality and changing population demographics over time. RESULTS: During the first 9 months of the pandemic, the values of per capita alcohol, essential and non-essential sales were, respectively, 13.2% higher, 3.6% higher and 13.1% lower than the average values during the same period in the prior 3 years. Interrupted time series models showed significant level change for the value of monthly per capita alcohol sales (+$4.86, 95% CIs: 2.88, 6.83), essential sales (-$59.80, 95% CIs: - 78.47, - 41.03) and non-essential sales (-$308.70, 95% CIs: - $326.60, - 290.79) during the pandemic. Alcohol sales were consistently elevated during the pandemic, and the pre- and post-pandemic slopes were comparable. In contrast, essential and non-essential retail sales declined in the early months of the pandemic before returning to regular spending levels. CONCLUSION: During the first 9 months of the pandemic, per capita alcohol sales were moderately elevated in Canada. In contrast, non-essential sales were lower than prior years, driven by large decreases during the initial months of the pandemic. These findings suggest that the pandemic was associated with increased population-level alcohol consumption, which may lead to increased alcohol-related harms. Ongoing research is needed to examine how factors, including pandemic-related stressors and specific alcohol sales-related policies, may have influenced changes in alcohol use and harms.

The prevalence and correlates of workplace infection control practices in Canada between July and September 2020.

BACKGROUND: There are important information gaps concerning the prevalence and distribution of infection control practices (ICPs) within workplaces continuing to operate during the COVID-19 pandemic. DATA AND METHODS: To address these gaps, this paper examines the prevalence of workplace ICPs among employed respondents to Statistics Canada's Labour Force Survey in the months of July, August and September 2020 (n = 53,316). The article also seeks to identify sociodemographic, occupational and workplace factors associated with the level and type of workplace ICPs. ICPs included the reorganization of the workplace to allow for physical distancing, increased access to hand sanitizer or handwashing facilities, enhanced cleaning protocols and access to personal protective equipment. Multivariable regression models were used to examine the number of ICPs in place and the absence of specific ICPs. RESULTS: Generally high levels of reported protections among workers (15% of the sample had three ICPs and 72% had four or more ICPs) were observed. However, certain subgroups of workers were less likely to have ICPs in place. These included workers who were male; those with lower levels of education, shorter job tenure, or non-permanent work; and those working in the agricultural, construction, transportation and warehousing, and education industries. INTERPRETATION: In a large sample of Canadian employees, generally high levels of workplace ICPs to reduce the transmission of COVID-19 were observed. Groups with lower levels of ICPs included workers at the start of their employment, workers with low levels of education, and certain industry groups.

COVID-19 Workplace Outbreaks by Industry Sector and Their Associated Household Transmission, Ontario, Canada, January to June, 2020.

OBJECTIVE: To analyze workplace outbreaks by industry sector in the first wave of the pandemic, and associated household cases. METHODS: Number, size, and duration of outbreaks were described by sector, and outbreak cases were compared to sporadic cases in the same time frame. Address matching identified household cases with onset ≥2 days before, ≥2 days after, or within 1 day of the workplace outbreak case. RESULTS: There were 199 outbreaks with 1245 cases, and 68% of outbreaks and 80% of cases belonged to (1) Manufacturing, (2) Agriculture, Forestry, Fishing, Hunting, (3) Transportation and Warehousing. There were 608 household cases associated with 339 (31%) outbreak cases, increasing the burden of illness by 56%. CONCLUSIONS: Workplace outbreaks primarily occurred in three sectors. Prevention measures should target industry sectors at risk to prevent spread in and out of the workplace.