What is COVID-19? Transmission, symptoms and warning signs
COVID-19 is caused by SARS-CoV-2. It spreads mainly through respiratory particles; symptoms range from none or mild illness to severe disease.
Transmission
SARS-CoV-2 spreads mainly through respiratory particles released when an infected person breathes, speaks, coughs or sneezes. Risk rises with close, prolonged contact, particularly indoors with poor ventilation.
Common symptoms
Fever, cough, sore throat, runny nose, fatigue, headache, body aches, altered smell or taste, and gastrointestinal symptoms can occur. Symptoms alone cannot reliably distinguish COVID-19 from other respiratory infections.
When to get urgent help
Seek urgent medical care for trouble breathing, chest pain, confusion, inability to wake, bluish lips or skin, or rapid deterioration. Older adults and people with underlying conditions should contact a clinician early if they become unwell.
Sources
Related guides
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This content is general information, not a diagnosis or individual medical advice. Seek urgent help for severe or rapidly worsening symptoms.