National surveillance for Coronavirus disease (COVID-19)

Last Updated: March 8, 2021

Purpose

This document outlines the recommended goals, objectives, and activities for COVID-19 surveillance in Canada. These guidelines are based on current available scientific evidence and expert opinion and are subject to change as new information becomes available. They should be read in conjunction with relevant provincial/territorial (P/T) and local legislation, regulations and policies. These guidelines have been developed based on the Canadian situation; therefore, they may differ from surveillance guidance developed by other countries.

Background

On March 11, 2020 the World Health Organization declared a global pandemic of COVID-19. Since then, community transmission of COVID-19 has been established and continues to be reported throughout Canada. The systematic, ongoing collection and analysis of COVID-19 related information must be conducted in a timely and organized manner to inform public health decision making. The Public Health Agency of Canada (PHAC) has developed a passive, population based surveillance system to monitor COVID-19 activity in Canada.

For information regarding the current status of COVID-19 in Canada, visit the Public Health Agency of Canada's Coronavirus Disease (COVID-19): Outbreak update website.

Surveillance goals and objectives

The primary goal of public health response in Canada is to contain the epidemic and mitigate health effects of the epidemic on Canadians. The secondary objective is monitor the clinical and epidemiologic features of COVID-19 including variants of concern to better inform prevention and control efforts.

The following national surveillance objectives have been developed:

1. Monitor the activity of COVID-19 to ensure rapid detection, isolation, testing, and case management.
2. Contribute to evidence on the epidemiological characteristics of the disease (e.g., clinical features and progression, morbidity, mortality, vulnerable populations).
3. Monitor and assess COVID-19 transmission and the relative impact and burden of disease.
4. Notify and disseminate information to stakeholders in order to facilitate timely and appropriate public health activities.
5. Provide evidence to support the implementation of public health interventions (including immunization) and the evaluation of their impact.
6. Identify knowledge gaps that would better inform public health response.
7. Contribute to global surveillance activities.
8. Monitor variants of concern as they are identified internationally or domestically.

As this epidemic continually evolves in Canada and globally, these surveillance objectives may change accordingly.

Case finding and investigation

Case definitions

PHAC has developed the national COVID-19 surveillance case definitions for classification and reporting COVID-19 probable and confirmed cases, as well as resolved and deceased cases. These definitions are available and updated as necessary.

Case identification and contact management

Classification of an individual as a probable or confirmed COVID-19 case is an immediate trigger to initiate the public health case management. Detailed recommendations for case management are found in the Updated: Public health management of cases and contacts associated with COVID-19.  

For the purpose of national surveillance, demographic, clinical, epidemiologic, and laboratory information on all probable and confirmed cases should be collected as outlined in PHACs COVID-19 case report form (PDF).

National reporting

Provinces and Territories voluntarily report confirmed and probable cases of COVID-19 to PHAC. Early reporting of investigation results of COVID-19 cases in Canada is strongly encouraged, even before analyses are complete. Preliminary data can be critical in the assessment of spread within Canada and are used to inform decision-making.

Required data elements

Provinces and Territories are asked to provide required data elements (as found on COVID-19 case report form and summarized in Box 1). A data dictionary  is available that outlines the definitions, format and values for each variable as part of the case report form.

Box 1. Required data elements for national reporting

• Reporting province/territory
• Surveillance case classification (confirmed vs. probable)
• Case details (age, sex, gender, race, etc.)
• Occupation
• Symptom onset date
• Pre-existing conditions and risk factors
• Clinical course and outcomes (hospitalization, ICU admission, resolved case, death)
• Exposure (travel, close contacts, exposure settings, etc.)
• Laboratory information (date and type of specimen collection, type of test, sequencing)
• Vaccination history information (vaccination status, vaccine received, etc.)

How to report

Data are submitted via an electronic extract from a provincial/territorial information system.

Useful links

• Government of Canada: Coronavirus disease (COVID-19): Outbreak update
• Government of Canada: COVID-19 signs, symptoms and severity of disease: A clinician guide
• Government of Canada: Testing for COVID-19: Importance
• World Health Organization: Coronavirus disease (COVID-19)
• European Centre for Disease Control: COVID-19
• Centre for Disease Control: Coronavirus Disease 2019