Map of Simcoe Muskoka

Infectious Diseases

Technical Notes and Definitions

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COVID-19 cases represent people whose residential address is in Simcoe Muskoka at the time of their investigation, not the location of the hospital. Cases whose residence is outside of Ontario are assigned to the health unit that is actively following up with the individual. Cases only include those that meet the definition for confirmed case classification as per the Ministry of Health Case Definition Coronavirus Disease (COVID-19) document.

Please note that confirmed re-infections, that is, where an individual has had more than one COVID-19 infection upon public health investigation, are counted as separate cases.

COVID-19 hospitalizations represent cases whose residential address is in Simcoe Muskoka regardless of where they are hospitalized, and who are being managed by Simcoe Muskoka District Health Unit. Cases who are residing and hospitalized outside of Simcoe Muskoka but who have been transferred to a local hospital, are excluded if they are not investigated by our health unit.

Hospital occupancy data included in the SMDHU Monitoring Dashboard represent all people who are admitted to local hospitals regardless of whether their residential address is in Simcoe Muskoka or not. People residing in Simcoe Muskoka who are admitted to hospitals outside of our region are excluded. This is different from the COVID-19 hospitalization numbers, which count hospitalizations among people who reside in Simcoe Muskoka regardless of where they are hospitalized.

Please note that 95% confidence intervals are not included on the charts and tables for simplicity; however, statistical significance between groups (e.g. geographic areas and age groups) was determined by non-overlapping confidence intervals.

Data Sources:

  • Confirmed COVID-19 cases: Public Health Case and Contact Management (CCM) Solution
  • Confirmed COVID-19 outbreaks: Public Health Case and Contact Management (CCM) Solution and the Integrated Public Health Information System (iPHIS).
  • COVID-19 testing data: Ontario Laboratories Information System (OLIS).
  • COVID-19 immunizations: COVaxON
  • Hospital occupancy: Daily Bed Census Summary for acute care capacity and the CRITICALL Ontario Critical Care Information System (CCIS) for ICU and ICU-ventilated bed capacity.
  • COVID-19 local impact survey result: an online survey to learn about the financial, mental, physical and social impacts of the pandemic on the local population.

Terminology/ Definitions

Case Fatality Rate (CFR): The percentage of people diagnosed with a disease that die within a certain time after diagnosis (usually prior to recovery).

Median Reproductive Number (Rt): The average number of secondary cases that each infected individual would infect if the conditions remained as they were at time ‘t’. R(t) is presented as a 7-Day Rolling Average of Median value of R(t), adjusted for reporting lag times. It is calculated using symptom onset date. A reproduction number greater than 1 means that the epidemic is growing, while a reproduction number less than 1 means the epidemic is slowing and containment/mitigation efforts may be working to keep control of epidemic.

Percent Positivity: Percent positivity represents the percentage of completed COVID-19 tests that are positive for the COVID-19 virus, over a defined period of time. A low percent positivity rate indicates the outbreak is under control, given more testing is finding a smaller proportion of positives.

Variant Definitions

Variant: Variant of Concern cases and Positive Screen cases as combined.

 

Variant of Concern (VOC): A confirmed case of COVID-19 with whole-genome sequencing results matching it to a known variant of concern, or has tested positive for a specific combination of mutations that are highly correlated with a known variant of concern.

 

  • Variants of concern have one or more mutations in the COVID-19 virus (SARS-CoV-2) that differentiates it from other versions of the virus that are being spread in the community, and have specific traits that are concerning for human health. Currently, the health unit reports on three variants of concern (B.1.1.7 (UK), P.1 (Brazil) and B.1.351 (South Africa).
  •  

  • Variants of concern for COVID-19 to date have shown one or more of the following traits:
    • Increases in how easily the virus can be spread
    • Increased disease severity
    • Changes in our ability to diagnose (test) for the virus
    • Decreased effectiveness of treatments and/or vaccines

 

Note: Changes in the genetic makeup of the COVID-19 virus (SARS-CoV-2) is expected and have been emerging and circulating throughout the world throughout the pandemic.

More information on variants of concern can be found on our website here.

 

Positive screen: A confirmed case of COVID-19 that has been tested for mutations known to be found in one or more identified variants of concern (see variant of concern above). Subsequent testing is required to identify the specific variant of concern. Locally, mutations of interest that are routinely tested for are N501Y and E484K.

 

Starting on March 26, 2021 due to changes in testing methods at Public Health Ontario, B.1.1.7 cases will include confirmed B.1.1.7 lineage based on whole genome sequencing, and presumed B.1.1.7 cases based on a positive PCR test for the N501Y mutation and a negative PCR test for the E484K mutation. This has resulted in a large number of cases previously reported as screened positive being re-assessed as B.1.1.7 variant cases. This aligns with reporting being done by Public Health Ontario. Samples which screen positive for both the N501Y and E484K mutations continued to move forward with whole genome sequencing to identify specific variants. Additional details about Variant of Concern testing are available from Public Health Ontario.

 

Immunization Definitions

Vaccine Coverage (1st Dose): The percent of individuals residing in Simcoe Muskoka that received their first dose of any COVID-19 vaccine, regardless of where they received their vaccine in Ontario.

Vaccine Coverage (2nd Dose): The percent of individuals residing in Simcoe Muskoka that received their second dose of any COVID-19 vaccine, regardless of where they received their vaccine in Ontario.

Hospital Occupancy Definitions

Acute Care: The percent of all acute care beds in Simcoe Muskoka hospitals that are occupied on the most recent reporting date. This includes occupied beds that have been opened for use in the Pandemic Response Unit at Royal Victoria Regional Health Centre.

 

Intensive Care Unit (ICU) beds: The percent of all intensive care unit (ICU) beds in Simcoe Muskoka hospitals that are occupied on the most recent reporting date. This is restricted to medical, surgical and cardiovascular ICU units, and excludes neonatal and incremental (surge) ICU beds. The number of ICU beds at a hospital includes both ventilated and non-ventilated beds.

 

ICU-Ventilated Beds: The percent of all ventilated beds in intensive care units (ICU) in Simcoe Muskoka hospitals that are occupied on the most recent reporting date. This is restricted to medical, surgical and cardiovascular ICU units, and excludes neonatal and incremental (surge) ICU beds.

Case Type Definitions

Active cases are confirmed COVID-19 cases that are currently self-isolating, are under isolation precautions or are in hospital (including those in an ICU bed or on a ventilator). Excludes those with unknown status.

 

Sporadic cases are those not associated with an outbreak at an institution, workplace, community setting, educational setting or congregate setting in Ontario. These infections are usually acquired from travel, within the community or from close contact with a known case.

 

Institutional outbreak cases are COVID-19 cases that are linked to long-term care homes, retirement homes, hospitals or, correctional facilities.Applies to residents, staff, volunteers and third-party service providers.Institutions may be located in Simcoe Muskoka or in other health unit jurisdictions. The health unit is only able to comment on institutional outbreaks in our area.

 

Workplace outbreak cases are confirmed COVID-19 cases that are linked to a place of employment that is not open to the public (e.g., farms, food processing plants, manufacturing). Excludes institutions, congregate settings, educational settings and community setting workplaces.Applies to employees and employers. Based on epidemiological investigation of cases in employees of a workplace who worked in proximity and at the same time of other confirmed cases. Workplaces may be located in Simcoe Muskoka or in other health unit jurisdictions. The health unit is only able to comment on workplace outbreaks in our area.

 

Community outbreak cases are confirmed COVID-19 cases linked to workplaces that are open to the public (e.g., restaurants, bars, funeral homes, gyms, community centres, personal service settings etc.), community events (e.g., concerts) or social gatherings.Based on epidemiological investigation of cases that were in close proximity and at the same time of other confirmed cases at the facility, event or gathering. These community settings may be located in Simcoe Muskoka or in other health unit jurisdictions. The health unit is only able to comment on community setting outbreaks in our area.

 

Congregate settings outbreak cases are confirmed COVID-19 cases linked to settings in which people temporarily or permanently reside such as group homes, supportive housing or shelters.Applies to residents and staff. Based on epidemiological investigation of cases in residents/staff of a congregate setting who were in proximity and at the same time of other confirmed cases. Congregate settings may be located in Simcoe Muskoka or in other health unit jurisdictions. The health unit is only able to comment on congregate setting outbreaks in our area.

 

Educational settings outbreak cases are confirmed COVID-19 cases linked to child care centres, elementary and secondary schools as well as trades school, college and university. Applies to students and staff. Based on epidemiological investigation of cases in students/staff of an educational setting who were in proximity and at the same time of other confirmed cases. Educational settings may be located in Simcoe Muskoka or in other health unit jurisdictions. The health unit is only able to comment on educational setting outbreaks in our area.

 

For all of the above, only cases where the Simcoe Muskoka District Health Unit is the investigating health unit (previously referred to as responsible health unit) are included.

Status definitions

Recovered: a confirmed COVID-19 case who is 14 days past symptom onset, without fever, has improving symptoms and is not currently hospitalized.

 

Hospitalized Never in ICU: confirmed COVID-19 case that has ever been admitted to hospital but has never been admitted to an intensive care unit nor been on a ventilator in hospital.

 

Hospitalized - ICU: confirmed COVID-19 case that has ever been admitted to an intensive care unit or been on a ventilator in hospital.

 

Total Hospitalized: the number of confirmed COVID-19 cases who have ever been admitted to hospital. This includes patients who have ever been admitted to an intensive care unit and those that have ever been on a ventilator in hospital.

 

Active or Current Hospitalization: a confirmed COVID-19 cases who has not recovered and is currently admitted to hospital. This includes patients who are currently admitted to an intensive care unit and those currently on a ventilator in hospital.

 

Self-Isolating: A confirmed COVID-19 case who has not recovered and is not currently hospitalized that is self-isolating at home.

 

Isolation Precautions: A confirmed COVID-19 case who has not recovered and is not currently hospitalized resides in an institution (e.g. a long-term care home) and is under isolation precautions within the institution.

Acquisition definitions

Travel: most likely acquisition of illness is from travel outside of Ontario.

 

Close Contact: most likely acquisition of illness is from close contact with another confirmed COVID-19 case. Exposures include: close personal contact, shared airspace, and household contact. This excludes anyone with travel history within 14 days of symptom onset.

 

Community-Acquired: signifies a sporadic case in an individual where most likely acquisition of illness is from somewhere within the community but not associated with a community outbreak. This also excludes transmission due to travel and due to close contact with a known case.

 

Educational Setting Outbreak-Related: a confirmed COVID-19 case that is a student/attendee or staff of an educational setting (childcare centres, elementary and secondary schools as well as trades schools colleges and universities) where an outbreak has been declared.

 

Institutional Outbreak-Related: a confirmed COVID-19 case that is a resident or staff member of a long-term care institution, retirement home, correctional facility, or hospital. These types of transmissions are often referred to as nosocomial.

 

Workplace Outbreak-Related: multiple confirmed COVID-19 cases in employees of a workplace that is not open to the public and who worked in proximity and at the same time of other confirmed cases and, based on epidemiological investigation, a higher level of disease transmission within the workplace than what would be expected given current local COVID-19 activity and incidence in the community.

 

Community Outbreak-Related: multiple confirmed COVID-19 cases in individuals who attended a community event or social gathering at the same time of other confirmed cases and, based on epidemiological investigation, were deemed to be potentially infectious during the event or may have acquired the infection while attending the event.

 

Congregate Setting Outbreak-Related: a confirmed COVID-19 case that is a resident or staff member of facilities in which people temporarily or permanently reside such as group homes, supportive housing or shelters. These cases are not included in either the institutional or workplace outbreak cases.

 

Undetermined: most likely acquisition of illness is not clear and investigation is complete.

 

Under Investigation: a confirmed COVID-19 case with current status under investigation at the time of reporting.

 
Page last updated May 6, 2021