October 2024 Enhancements to the Ontario Respiratory Virus Tool

Public Health Ontario (PHO) has updated the Ontario Respiratory Virus Tool (ORVT) to provide more comprehensive, and detailed data on respiratory virus activity in Ontario for the 2024-2025 season. Key enhancements include:

• The summary section has been expanded to include:
• Projections of COVID-19, influenza, and RSV activity for the next two weeks, based on highlights from PHO’s Integrated Respiratory Virus Risk Indicators surveillance report.
• Influenza strain details describing influenza subtype, strain characterization and antiviral susceptibility information.
• Streamlined the laboratory testing data for the 2024-2025 season:
• Ontario Laboratories Information System (OLIS) data is now used to present laboratory testing data for RSV, influenza, COVID-19 and other respiratory viruses (from June 23, 2024), including public health unit and age group breakdowns.
• The tool will continue to present laboratory testing data from PHO’s laboratory and Public Health Agency of Canada for previous seasons.
• A new COVID-19 episodes indicator to approximate COVID-19 cases, referring to individuals with a positive COVID-19 PCR test in OLIS, provided they did not have another positive test result in the last 90 days (data starting August 27, 2023).
• Note: COVID-19 episodes are not the same of COVID-19 cases since it does not include all laboratory tested individuals that met the provincial case definition for COVID-19. Historical COVID-19 cases data are available in the tool up to June 1, 2024.
• The Outbreaks section has been expanded, with the following indicators now available to describe outbreak severity:
• Case, hospitalization and death counts
• Attack, hospitalization and fatality rates
• Duration

Why has the primary source for laboratory testing data changed with this iteration of the tool?
We have streamlined laboratory testing data. For the 2024-2025 season, Ontario Laboratories Information System (OLIS) data is now used to present laboratory testing data for RSV, influenza, COVID-19 and other respiratory viruses (from June 23, 2024), including public health unit and age group breakdowns. OLIS is a comprehensive database that includes lab test orders and results from hospitals, community labs, and public health labs. The tool will continue to present laboratory testing data from PHO’s laboratory and Public Health Agency of Canada for previous seasons.

What is the difference between a COVID-19 case and episode?
COVID-19 episodes refer to individuals with a positive COVID-19 PCR test in OLIS, provided they did not have another positive test result in OLIS in the last 90 days. COVID-19 episodes are presented in the tool starting August 27, 2023. COVID-19 episodes are not the same of COVID-19 cases since they do not include all laboratory tested individuals that met the provincial case definition for COVID-19. However, COVID-19 episodes can be used to provide an approximation of COVID-19 cases based on data from OLIS. Historical COVID-19 cases data from CCM are available in the tool up to June 1, 2024.

What are some other important respiratory surveillance resources?
Integrated Respiratory Virus Risk Indicators surveillance report: This report provides short-term projections of COVID-19, influenza, and respiratory syncytial virus (RSV) activity and risk of related severe viral respiratory disease (i.e., hospitalizations related to the three viruses) in the pediatric and general adult populations.

SARS-CoV-2 Genomic Surveillance in Ontario surveillance report: This report summarizes the results of SARS-CoV-2 whole genome sequencing, including variants of concern and variants of interest, conducted by the Ontario COVID-19 Genomics Network.

How often is the tool updated?
The tool will be updated weekly on Fridays at 11:30 a.m., with data up until the previous Saturday.

What can I do if I can’t find the information that I am looking for?
To see information on source data, methods, assessment criteria, citations and more, explore the Technical Notes. To learn how to navigate the tool, check out the User Guide.