SUBMITTED BY
Epidemiology and Evaluation Department
DATE
April 21, 2022
SUBJECT
COVID-19 Surveillance and Epidemiology – March, 2022
BACKGROUND
Overview
The Epidemiology & Evaluation department conducts on-going population health assessment and surveillance. The data and surveillance for COVID-19 plays an integral role in understanding and managing the pandemic locally. The evidence provides information on how the pandemic has and is evolving, assessing the risk and severity, and assists in the development of timely interventions to limit further spread in the community.
Due to the recent surge in Omicron cases and changes in eligibility for testing, testing capacity is limited and case, contact, and outbreak management has been modified to focus on high-risk settings. As a result, case counts in the report are an underestimate of the true number of individuals with COVID-19 in Windsor-Essex County and may impact data completeness. Please interpret these data accordingly. Due to these changes, data from before December 31, 2021 should not be compared to data after the testing changes.
Trends
In the month of March, the health unit reported 2,353 confirmed high-risk cases of COVID-19. As the weeks progressed in March, the weekly high-risk incidence rate increased from 124.0 cases per 100,000 population (Week 9) to 145.1 cases per 100,000 population (Week 13).
In-Patient and ICU Admissions
In March, in-patient COVID-19 hospitalizations began to increase in Windsor-Essex County. A total of 155 new COVID-19 related patients were admitted to local hospitals.
Percent Positivity
Locally, Windsor-Essex County continued to experience a week-over-week increase in percent positivity in March after observing the opposite for February. As the month drew to a close, the local percent positivity rate for COVID-19 rose to approximately 19.3% in the last week of the month. It is also important to note that these were for high-risk individuals that were eligible for testing.
Wastewater Surveillance
For the month of March, viral signal for COVID-19 in wastewater intensified as the month drew to a close. Current levels are beginning to reach levels observed during the onset of the Omicron wave in December 2021.
Outbreaks
In the month of March, 21 outbreaks were declared in high risk settings compared to the 24 outbreaks in February. This includes seven outbreaks in long-term care and retirement homes, four in hospital settings, and ten in other congregate settings. As of March 31st, there were 16 active outbreaks in the Windsor-Essex County region.
Deaths
For the month of March 2022, 16 deaths were reported that were attributed to COVID-19. This represents a 45% decline in comparison to the deaths reported in February.
DISCUSSION
With the changes in testing eligibility, and guidance with case, contact and outbreak management, the health unit has modified its public reporting to better understand the burden of illness locally. New indicators, such as wastewater data, have been included as a proxy indicator for COVID-19 case counts, which are underestimated. The health unit will continue to monitor and provide epidemiological expertise on COVID-19 to internal leadership, community partners, and residents to support evidence-informed decision-making. This includes daily epidemiological updates, weekly epidemiological presentations to the community and supporting policy decisions through data driven approaches.