Map of Simcoe Muskoka

Infectious Diseases

Variants of Concern and Mutations of Interest (VOC/MOI)

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  • The Alpha (B.1.1.7) and Delta (B.1.617.2) variants of concern (VOCs), are the most identified VOCs in Simcoe Muskoka. As of October 20, 2021 there are a total of 6,321 variant cases (Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2)) and Mutations of Interest (MOI)/screened positive cases). As of June 17, 2021, the Simcoe Muskoka District Health Unit, along with 10 other Ontario public health units, was declared a hot spot for the Delta (B.1.617.2) VOC.
  • As of October 20, 2021, there are four active COVID-19 outbreaks with known variant cases.
  • The 7-day moving average of new VOC/screened positive cases dropped by half from 25 cases per day in early September to 12 cases per day by early October; however, the average number of cases has been increasing slightly since then (Note: not including the most recent days due to delays).
  • Starting in June, the proportion of COVID-19 cases identified as the Delta (B.1.617.2) VOC began increasing, while the proportion of cases identified as the Alpha (B.1.1.7) VOC began decreasing. Delta (B.1.617.2) has been the dominant VOC in Simcoe Muskoka since mid-June and has been identified in over 80% of cases since mid-August (excluding the most recent week due to reporting delays).
  • All B.1.617 cases are currently presumed to be of the Delta (B.1.617.2) lineage as it is the dominant B.1.617 strain in Ontario.
  • Estimates suggest that VOCs are more contagious than the original COVID-19 strain, and that they are associated with an increased risk of hospitalization, intensive care unit (ICU) admission and death due to COVID-19.
  • For outbreaks in which one or more cases have been laboratory confirmed to have a VOC, there is a higher degree of certainty that other cases in the outbreaks will also have the VOC.
  • Screening practices for VOCs and mutations of interest may vary at the discretion of Public Health Ontario, based on public health priorities and public health lab capacity. See Technical Notes for more details
  • Emerging VOCs have mutations in the virus genome that alter the characteristics and cause the virus to act differently in ways that are significant to public health. It’s important to understand that genetic mutations are expected, and some variants can spread and become predominant while others subside.
  • Public health measures needed to help address the variant are the same as those in place right now.

Variant Outbreaks with Variants of Concern Cases and/or Positive Screen Cases, Simcoe Muskoka

Variant Outbreaks with Variants of Concern Cases and/or Positive Screen Cases Declared by Week, Simcoe County and Muskoka District

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Variant of Concern Cases and/or Positive Screen Cases by Type of Case, Simcoe County and Muskoka District

7 Day Rolling Average of New COVID-19 Cases with a Variant of Concern (VOC) or a Screened Positive Result, Simcoe Muskoka

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Weekly COVID-19 Variants of Concern (VOCs) by Percent or Counts, Simcoe Muskoka

Links to Related Information and Resources

Technical Notes and Definitions

Please see Technical Notes and Definitions here.

Page Last Modified: October 20, 2021