# SARS-CoV-2 and COVID-19 pandemic overview

> Live situation record from CLSTR: https://clstr.news/situations/sars-cov-2-and-covid-19-pandemic-overview
> Updated: 2026-10-18T23:14:58.000Z. Sources: 12. Developments: 2.

COVID-19 is a contagious disease caused by the SARS-CoV-2 coronavirus that initiated a global pandemic in January 2020. Symptoms vary and include fever, fatigue, cough, breathing difficulties, and loss of taste or smell, typically appearing within one to fourteen days of exposure. At least one-third of infected individuals do not show noticeable symptoms.

Among symptomatic patients, approximately 81% develop mild to moderate symptoms, 14% develop severe symptoms such as hypoxia, and 5% develop critical symptoms including respiratory failure or shock. Older populations face a higher risk of severe illness. Transmission occurs through inhaled infectious particles or contact with the eyes, nose, or mouth. Individuals can remain contagious for up to 20 days, and some patients may experience long-term effects known as ‘long COVID’ that persist for months or years.

## Claims

- COVID-19 is caused by the SARS-CoV-2 coronavirus. (corroborated by 3 sources)
- The disease spread worldwide in January 2020, leading to a pandemic. (corroborated by 3 sources)
- At least one-third of infected individuals do not show noticeable symptoms. (corroborated by 3 sources)
- Of symptomatic patients, 81% experience mild to moderate symptoms, 14% experience severe symptoms, and 5% experience critical symptoms. (corroborated by 3 sources)
- Infected individuals can remain contagious for up to 20 days. (corroborated by 3 sources)

## Timeline

### 2026-10-18: COVID-19: Overview of SARS-CoV-2 symptoms and transmission

COVID-19, caused by the SARS-CoV-2 virus, triggered a global pandemic in January 2020. Symptoms range from mild to critical, with many infected individuals remaining asymptomatic.

5 sources. https://clstr.news/cluster/covid-19-overview-of-sars-cov-2-symptoms-and-transmission-1

### 2026-10-16: COVID-19 overview and SARS-CoV-2 characteristics

COVID-19, caused by the SARS-CoV-2 virus, is a contagious disease that led to a global pandemic in early 2020. Symptoms range from mild to critical, and individuals can remain contagious for up to 20 days.

7 sources. https://clstr.news/cluster/covid-19-overview-and-sars-cov-2-characteristics

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Cite as: SARS-CoV-2 and COVID-19 pandemic overview. CLSTR, https://clstr.news/situations/sars-cov-2-and-covid-19-pandemic-overview