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August 1, 2026Short & citedBlog
Civic Viewpoint.
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Field Notes • Medicine & Health

COVID-19

COVID-19 is an infectious disease caused by the SARS-CoV-2 coronavirus.

Updated August 1, 20261 min readCited sources

COVID-19 is an infectious disease caused by the SARS-CoV-2 coronavirus. It continues to circulate globally as a significant public health concern.

What it is

COVID-19 is caused by the SARS-CoV-2 virus and spreads through infectious respiratory particles in the air from infected people. Symptoms can range from mild illness to severe disease and may change with new variants.

Key details

Common symptoms include fever, cough, tiredness, sore throat, shortness of breath, congestion, headache, body aches, diarrhoea, and loss of taste or smell. Symptoms typically appear within 5–6 days after infection but can take up to 14 days. Many people recover within a few weeks, but some experience prolonged illness. Reinfection is possible because immunity is not permanent and new variants continue to emerge.

Why it matters

COVID-19 remains a public health concern globally and in Canada. Vaccines are available and reduce severe illness, but protection against infection can wane. Canadian agencies continue to track symptoms, variants, and transmission patterns.

In short

  • COVID-19 is caused by SARS-CoV-2 and spreads through airborne particles.
  • Symptoms vary widely; most people recover within weeks, but reinfection is possible.
  • Vaccines help prevent severe disease, but protection can wane over time.
  • COVID-19 still circulates globally and is tracked by Canadian health agencies.
Canadian angle

COVID-19 remains relevant in Canada because Canadian public health agencies continue to track symptoms, variants, vaccination, and local transmission patterns.

Quick questions

What are the symptoms of COVID-19?
Common symptoms include fever or chills, cough, sore throat, tiredness, shortness of breath, congestion, headache, body aches, nausea, diarrhoea, and loss of taste or smell.
Can you get COVID-19 more than once?
Yes. Reinfection happens because immunity changes over time and new variants appear; prior infection does not guarantee permanent protection.
Is COVID-19 still a pandemic?
WHO states COVID-19 continues to circulate globally and remains a significant public health concern, though it is no longer described everywhere as an active pandemic.

Sources

  1. Centers for Disease Control and Prevention — https://www.cdc.gov/covid/signs-symptoms/index.html
    Supports: Symptoms, timing of symptom onset, severity range, and variant-related symptom changes.
  2. NHS — https://www.nhs.uk/conditions/covid-19/covid-19-symptoms-and-what-to-do/
    Supports: Common symptoms and typical recovery timeframe.
  3. World Health Organization — https://www.who.int/news-room/fact-sheets/detail/coronavirus-disease-(covid-19)
    Supports: Cause, common symptoms, ongoing global circulation, and public health significance.
  4. World Health Organization — https://www.who.int/health-topics/coronavirus
    Supports: Symptoms, incubation period, and serious symptoms.