COVID-19 Testing
During the COVID-19 pandemic, waking up with a cough or fever can send your mind racing. Should I take a test for SARS-CoV-2 (the virus that causes COVID-19)? Was I in contact with someone with COVID-19? Do I need to see a doctor?
It can be confusing to navigate what to do and when to seek urgent medical attention, so we have made this guide that answers questions about COVID-19 testing and explains what to watch out for and what actions to take.
Symptoms
The most common symptoms of COVID-19 are the usual flu symptoms, such as fever, tiredness, dry cough, difficulty breathing, aches and pains, nasal congestion, and a sore throat. However, COVID-19 infections can involve atypical symptoms such as loss of smell or taste, or gastrointestinal (GI) symptoms such as nausea, vomiting, or diarrhea. For more information, see COVID-19 and GI Symptoms.
Symptoms can range from mild to severe, or you could have no symptoms at all (asymptomatic) and still spread the virus. Generally, asymptomatic individuals are less contagious than those with symptoms, but may pass on the virus to others since transmission can occur through droplets in the air even with breathing. For information on how to reduce transmission, see COVID-19 Prevention.
As new variants keep arising, we must continue to take SARS-CoV-2 seriously, even considering that as of mid-November 2022, data show (the link will update as soon as new information is available.), that more than 86% of Canadians five years of age and older have had at least one dose of the vaccine and more than 84% are fully vaccinated. Over 8.5% of those aged 5 years and older have received a booster dose between August 1, 2022 and mid-October 2022.
People who are immunocompromised or taking medications that impair the immune system should take a COVID-19 test when symptoms are present. (e.g., some medications for inflammatory bowel disease [Crohn’s disease and ulcerative colitis], multiple sclerosis, lupus, alopecia areata, rheumatoid arthritis, psoriasis or psoriatic arthritis, and some oncology medications). If the test is positive, you should seek medical assessment and may require a COVID-19 treatment.
When to Self-Isolate and Rest
If you have mild symptoms, you should self-isolate, rest, and keep well hydrated, unless you fall in a group deemed by your local public health to be at higher risk for hospitalization. These individuals should seek medical assessment and advice on treatment options. Please see here for your province’s or territory’s criteria and how to access treatment. Even without a test, you should assume you are positive and follow this plan. Typically, you can manage mild symptoms at home using over-the-counter cold medications. Call your pharmacist for advice about which products might help to treat your specific symptoms and make you feel more comfortable. Some pharmacies offer delivery services to support patients who are self-isolating, so ask about that too.
When to Seek Medical Attention from Your Family Doctor
Seek a virtual or phone appointment with your family physician if you have a fever (>38.5°C) lasting longer than 72 hours, high fever (>40.5°C), severe sudden throat pain, prolonged congestion lasting longer than a week, difficulty breathing, double sickening (worsening symptoms after a few days of initial improvement), or low blood oxygen levels (less than 92%) when measured by a pulse oximeter.
For people at a high risk of hospitalization or death, treatments such as Paxlovid™ (ritonavir-boosted nirmatrelvir) can reduce the risk of severe infection and hospitalization. Some examples of features that may increase your risk include (but are not limited to):
- being under-vaccinated
- advanced age
- taking medications that significantly reduce your immune system
- having a condition that weakens your immune system
- certain cancer treatments and chemotherapies
- medical conditions such as obesity, diabetes, heart disease, kidney disease, chronic lung disease
- alcohol use disorder
- tobacco smoking
For more information, see Who is at Risk of Severe COVID-19?
When to Seek Emergency Medical Attention
Seek immediate medical attention at a hospital (call an ambulance, if necessary) if you develop severe, potentially life-threatening symptoms such as shortness of breath, chest pain or pressure, confusion, inability to wake up or stay awake, blue colouring in the face or lips, losing consciousness (fainting), pale, grey, or blue-coloured skin, lips or nail beds, or any sign that indicates a lack of oxygenation or significant breathing problems.
Testing
Taking a test when you have symptoms of COVID-19 infection is helpful in guiding your next steps and making decisions toward preventing its spread to others.
The Truth About Testing
Although the Public Health Agency of Canada keeps a close watch on all significant infections in Canada, the specific recommendations and steps for COVID-19 testing come from the provincial/territorial health authorities. Where you live, whether rural or urban, and the availability of services and test equipment, all influence what you have access to. What you hear on the news or via social media might not be relevant in the area where you live.
Most people with mild respiratory symptoms do not need a test. This is because knowing the result will typically not change the management plan, which is to self-isolate and continue to monitor and manage symptoms at home while taking steps to reduce the spread of the infection.
Types of COVID-19 Tests
When making decisions based on the outcome of a COVID-19 test, it is important to understand a bit about them. Here are the tests in use:
- Rapid Antigen Tests – also known as antigen tests, rapid tests, home tests, and self-tests – detect the presence of virus proteins. Rapid antigen tests are less expensive and give results within minutes, but they are less sensitive and can only detect infection when the volume of virus particles in the body (viral load) is high, as it is during the peak of active infection. These tests are more likely to give a false negative result. For guidance around rapid testing in the workplace, check out the Benefits of Rapid Testing from The Canadian Centre for Occupational Health and Safety.
- Molecular Tests – also known as nucleic acid amplification (NAAT) tests, ribonucleic acid tests, or polymerase chain reaction (PCR) tests – detect the virus’ genetic material. Molecular tests use different technologies, including reverse transcription polymerase chain reaction (RT-PCR or PCR), loop mediated isothermal amplification (LAMP), transcription mediated amplification (TMA) and strand displacement amplification (SDA). PCR testing is the gold standard for COVID-19 diagnosis and is the most used. This test is more sensitive than rapid antigen testing and can detect infection when the viral load is lower. That doesn’t mean the test is always right though. These tests might still deliver a false negative result in the initial or late stages of infection when the viral load is at its lowest, or if there was an error in sample collection. It could also deliver a positive result in the late stages of infection when an individual still has virus particles in their body but is likely no longer contagious. The PCR test is more expensive than the rapid antigen test and it can take up to three days to receive results.
- Antibody Tests do not diagnose or screen for an active infection but can detect antibodies to the virus in your blood, an indication that you have had a prior infection. Current antibody tests do this by detecting antibodies against the nucleocapsid protein found in patients who have had the COVID-19 infection. These antibodies are different from the antibodies your body makes when you receive a COVID-19 vaccine.
Where to Get a Test
Only those who develop symptoms of COVID-19 and want to confirm a positive or negative result should use a test. Depending on supply and demand in your community, you should be able to obtain free COVID-19 home test kits at your local pharmacy or public health office. Each kit comes with instructions on how to use the tests. Please consult a pharmacist if you have questions or concerns.
Alberta: https://www.albertahealthservices.ca/topics/Page17058.aspx
British Columbia: https://www2.gov.bc.ca/gov/content/covid-19/info/testing
Manitoba: https://www.gov.mb.ca/covid19/testing/index.html
New Brunswick: https://www2.gnb.ca/content/gnb/en/corporate/promo/covid-19/about-covid-19/testing-tracing.html
Newfoundland and Labrador: https://www.gov.nl.ca/covid-19/testing/who-should-get-tested/
Northwest Territories: https://www.nthssa.ca/en/covid-testing
Nova Scotia: https://www.nshealth.ca/coronavirustesting
Nunavut: N/A
Ontario: https://www.ontario.ca/page/covid-19-testing-and-treatment
Prince Edward Island: https://www.princeedwardisland.ca/en/information/health-and-wellness/covid-19-testing-in-pei?utm_source=ABACanada&utm_medium=Referral&utm_campaign=websitelisting
Yukon: https://yukon.ca/en/get-covid-19-test
Travelling
Travelling outside of Canada might require testing even when you are asymptomatic and may need to be carried out at a certified or accredited test site. In most cases, home test kits and rapid antigen self-test kit results are not sufficient for travel requirements. Currently, most provinces do not provide coverage for travel testing, and you will need to book with a private collection centre to test for COVID-19 before travelling, and pay a fee.
Conclusion
You are a priority for testing if you are at an elevated risk of complications and severe illness, as you might need a different management plan. This includes those who are moderately to severely immunocompromised, those 18 years of age and older who are unvaccinated or partially vaccinated, and those who live or work in high-risk settings. Check for your local eligibility requirements and availability of tests.
Updated: 2022-11-23
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