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.

(adapted from various government websites)
  • Most people with COVID-19 have mild illness and can recover at home without medical support. Follow health guidelines provided by your local health authority. It is best to isolate and not leave your home, except to get medical care. Do not visit public areas and wear a well-fitting mask when near others.
  • Get rest and stay hydrated. To help relieve symptoms, you may take over-the-counter medicines, such as acetaminophen. Check with your healthcare provider for your particular situation.
  • Call your health practitioner before you visit to get medical care and let the office know you have tested positive for COVID-19.
  • Avoid public transportation, ridesharing, or taxis and wear a mask if you must travel.
  • Separate yourself from other people and avoid physical contact.
  • As much as possible, stay in a specific room and away from other people and pets in your home. If possible, you should use a separate bathroom. If you need to be around other people or animals in or outside of the home, wear a mask.
  • Although not a requirement, it is best to inform your close contacts that they may have been exposed to COVID-19. As a general guide, an infected person can spread COVID-19 beginning 48 hours before the person has any symptoms or tests positive. By letting your close contacts know they may have been exposed to COVID-19, you are helping to protect everyone, and they may want to test for COVID-19.
  • If you can’t put on a mask (because of trouble breathing, for example), cover your coughs and sneezes in some other way. Try to stay at least 2 metres (6 feet) away from other people. This will help protect the people around you.

  • If you have symptoms and test negative, there may be a number of reasons for this:
    • You do not have a COVID-19 infection and there is another reason for the symptoms such as allergies, common cold, dust or contaminants in the air, etc.
    • Even though you may be infected with COVID-19, you may not test positive with the type of test you are using because it is not sufficiently sensitive, it is still early in the infection, or you may be performing the test incorrectly if you are using a home test kit. You can repeat the test to make sure.
    • False negatives are possible and the frequency of this is low and depends on the test kit you are using.

If you have IBD (including Crohn’s disease and ulcerative colitis), you might be taking drugs that affect how your immune system responds to infection. These could include biologic medications or other immunosuppressive or immunomodulating therapies (e.g., azathioprine, methotrexate). You should discuss this with your healthcare provider. If you develop respiratory symptoms, do not stop taking your IBD medications. This may sound counterintuitive as immunosuppressive therapies can reduce your ability to fight off infections but stopping your medication without any direct instruction from your healthcare provider can be dangerous and can lead to complications such as disease flares and hospitalization. If you are taking medications that suppress your immune system or are high risk for a severe infection or hospitalization from COVID-19, you should contact your healthcare provider if you test positive for COVID-19 and have symptoms. You may benefit from treatments available to you, but you need to start these treatments within five to seven days of the onset of symptoms.

Aside from staying on your existing medications and adhering to the information outlined above, the action plan to manage COVID-19 is similar to that for everyone else. However, the next time you have an appointment with your doctor, be sure to discuss vaccinations and what you should do if you develop COVID-19-like symptoms.

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:

  1. 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.
  2. 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.
  3. 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

Quebec: https://www.quebec.ca/en/health/health-issues/a-z/2019-coronavirus/testing-for-covid-19/get-covid-19-test

Saskatchewan: https://www.saskatchewan.ca/government/health-care-administration-and-provider-resources/treatment-procedures-and-guidelines/emerging-public-health-issues/2019-novel-coronavirus/testing-information

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

Sources

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