Importance: The emergence of SARS-CoV-2 Variants of Concern (VOC) across North America has been associated with concerns of increased COVID-19 transmission . Characterizing the distribution of VOCs can inform the development and implementation of policies and programs to address the prevention needs of disproportionately affected communities .
Objective: We compared per-capita rates of COVID-19 cases (overall and VOC) from February 3 , 2021 to March 10 , 2021, across neighborhoods in the health regions of Toronto and Peel, Ontario, by proportion of the population working in essential services and income .
Design: Descriptive epidemiological analysis, integrating COVID-19 surveillance and census data . Per-capita daily epidemic curves were generated using 7-days rolling averages for cases and deaths . Cumulative per-capita rates were determined using census-reported population of each neighbourhood .
Setting: The study setting was the city of Toronto and the region of Peel (the City of Brampton, Mississauga, and Caledon), Canadas largest cities with a combined population of 4.3 million . This area of Canada has had one of the highest incident rates of COVID-19 throughout the pandemic . Participants: We used person-level data on laboratory-confirmed COVID-19 community cases (N=22,478) and census data for neighborhood-level attributes . Exposures: We stratified neighbourhood using dissemination areas which represent geographic areas of approximately 400-700 individuals, into tertiles by ranking the proportion of population in each neighbourhood working in essential services (health, trades, transport, equipment, manufacturing, utilities, sales, services, agriculture); and the per-person equivalent household income . Main Outcome (s) and Measure (s): The primary outcomes were laboratory-confirmed COVID-19 cases overall and VOC positives by neighbourhood .
Results: During the study period, VOC cases emerged faster in groups with lowest income (growth rate 43.8% , 34.6% and 21.6% by income tertile from lowest to highest), and most essential work (growth rate 18.4% , 30.8% and 50.8% by tertile from lowest tertile of essential workers to highest tertile of essential workers). Conclusions and Relevance: The recent introduction of VOC in the large urban area of Toronto has disproportionately affected neighbourhoods with the most essential workers and lowest income levels . Notably, this is consistent with the increased burden of non-VOC COVID-19 cases suggesting shared risk factors . To date, restrictive public health strategies have been of limited impact in these communities suggesting the need for complementary and well-specified supportive strategies including vaccine prioritization to address disparities and overall incidence of both VOC and non-VOC COVID-19.