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

> Live situation record from CLSTR: https://clstr.news/situations/covid-19-pandemic-and-sars-cov-2-characteristics
> Updated: 2026-09-14T20:56:57.000Z. Sources: 10. Developments: 2.

COVID-19 is a contagious disease caused by the SARS-CoV-2 coronavirus that resulted in a global pandemic beginning in January 2020. Symptoms range from mild to critical, with approximately one-third of infected individuals remaining asymptomatic. Among symptomatic cases, 81% experience mild to moderate symptoms, 14% develop severe symptoms such as hypoxia, and 5% face critical conditions like respiratory failure or organ dysfunction. Older populations are at a higher risk for severe illness.

Transmission occurs through respiratory or airborne particles in indoor settings or via contact with contaminated surfaces. Individuals may remain contagious for up to 20 days. Some patients experience ‘long COVID,’ involving long-term effects that can persist for months or years. Diagnostic methods typically include detecting nucleic acid through RT-PCR or RT-LAMP via nasopharyngeal swabs.

## Timeline

### 2026-09-14: COVID-19 and the SARS-CoV-2 virus

COVID-19 is a contagious disease caused by the SARS-CoV-2 virus. It can cause symptoms ranging from mild to critical, with some patients experiencing long-term effects known as long COVID.

3 sources. https://clstr.news/cluster/covid-19-and-the-sars-cov-2-virus-4

### 2026-09-11: COVID-19 pandemic overview and clinical characteristics

COVID-19, caused by the SARS-CoV-2 virus, is a contagious disease that led to a global pandemic in 2020. Symptoms range from mild to critical, with long-term effects possible for some patients.

7 sources. https://clstr.news/cluster/covid-19-pandemic-overview-and-clinical-characteristics

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