# COVID-19 pandemic overview

> Live situation record from CLSTR: https://clstr.news/situations/covid-19-pandemic-overview
> Updated: 2026-08-25T09:53:01.000Z. Sources: 21. Developments: 2.

COVID-19 is a contagious disease caused by the SARS-CoV-2 coronavirus that initiated a global pandemic in January 2020.

Symptoms typically appear one to fourteen days after exposure and include fever, fatigue, cough, breathing difficulties, and loss of taste or smell. While approximately one-third of infected individuals are asymptomatic, those who do develop symptoms generally experience mild to moderate cases (81%), severe symptoms (14%), or critical conditions (5%).

Transmission occurs through the inhalation of infectious particles or contact with the eyes, nose, or mouth, with increased risk in indoor settings or close proximity. Individuals can remain contagious for up to 20 days. Diagnostic testing for the virus's nucleic acid includes methods such as RT-PCR and RT-LAMP.

## Claims

- COVID-19 is caused by the SARS-CoV-2 coronavirus. (corroborated by 12 sources)
- The disease spread worldwide in January 2020, leading to a pandemic. (corroborated by 12 sources)
- At least one-third of infected individuals do not show noticeable symptoms. (corroborated by 12 sources)
- Among symptomatic patients, 81% experience mild to moderate symptoms, 14% experience severe symptoms, and 5% experience critical symptoms. (corroborated by 12 sources)
- Individuals can remain contagious for up to 20 days, including those without symptoms. (corroborated by 12 sources)

## Timeline

### 2026-08-25: COVID-19 overview: SARS-CoV-2 transmission and symptoms

COVID-19, caused by the SARS-CoV-2 virus, became a global pandemic in January 2020. Symptoms vary from mild to critical, and transmission occurs through close contact or airborne particles.

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

### 2026-08-21: COVID-19 overview: symptoms, transmission, and long-term effects

COVID-19, caused by the SARS-CoV-2 virus, led to a global pandemic in early 2020. Symptoms vary from asymptomatic to critical, with long-term effects possible for some patients.

9 sources. https://clstr.news/cluster/covid-19-disease-characteristics-and-transmission-of-sars-cov-2

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Cite as: COVID-19 pandemic overview. CLSTR, https://clstr.news/situations/covid-19-pandemic-overview