Testing for COVID-19: Importance of testing and contact tracing
Always follow the instructions contained in your test kit or provided by your local health authority. The instructions are written specifically for that particular type of kit. If you take a sample in a different way, your test result may be invalid.
Get more information on our Authorized COVID-19 testing devices page.
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Why testing is important
Testing is the only way we can confirm if you have COVID-19. Knowing you're infected is important to protect your family and the people you encounter.
Contact your local health authority for advice about testing if you:
- think you may have COVID-19
- have been in contact with someone who has COVID-19
Testing helps reduce the spread of the virus. When someone tests positive for COVID-19, they can be isolated at home or, if needed, in a hospital.
Testing tells us:
- who has the infection
- where in our communities the virus is spreading
- how much the virus may be circulating in our communities
Testing is a key tool to:
- find and isolate people who have COVID-19, to prevent the spread to others and to prevent outbreaks
- follow up with close contacts of cases so that they can self-isolate, monitor for symptoms and get tested
- know how many people are infected, which helps us understand the level of risk in a community
- inform the public health actions that are put in place
- help us to better understand this virus
If you test positive for COVID-19, a public health official may ask you questions to collect important information about:
- your symptoms
- activities and travel you did before you tested positive
- all the people you may have been in close contact with while you were contagious
This is called contact tracing. It's a key public health measure to slow down or stop the spread of the virus.
By tracking down your contacts, public health officials can warn people that they may have been exposed to the virus. This helps your contacts take measures to self-isolate and monitor themselves for symptoms to prevent further spread.
The COVID Alert app was one of the public health tools available to help limit the spread of COVID-19. It helped to let people know of possible exposures before any symptoms appear.
- National overview of testing
- COVID-19: Prevention and risks
- COVID-19 Immunity Task Force
- COVID-19 Special Advisory Committee
- Measures to reduce COVID-19 in your community
- Collaboration with the Public Health Agency of Canada's National Microbiology Laboratory
- Information for patients: A guide to self-testing for COVID-19
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