How long is someone contagious with COVID-19?

Someone with COVID-19 may be contagious before symptoms, during illness, and sometimes for longer if recovery is delayed. The duration is not identical for everyone, so symptoms, test type, illness severity, and immune health all matter.

Contagious means able to pass the virus to another person. It is possible to spread COVID-19 without a cough, fever, or other clear warning. Risk rises with close, prolonged indoor contact, especially when air circulation is poor.

After infection, some people experience continuing tiredness, joint pain, or difficulty concentrating. Those symptoms can occur during recovery and do not, by themselves, prove that a person remains contagious. Learn about [Long COVID](/conditions/long-covid/) if symptoms persist.

The infected person should follow current local advice, stay home while acutely unwell, and use a well-fitting mask around others when contact cannot be avoided. Open windows or use effective ventilation, keep distance, and take extra care around older adults and people with serious health conditions.

Use separate personal items where practical, wash hands regularly, and clean shared high-touch areas. Testing can add information, but a single result cannot define contagiousness for every person.

Get emergency help if the person has severe breathing difficulty, persistent chest pain, sudden confusion, cannot stay awake, or develops pale, grey, or blue lips or skin. Seek prompt advice for worsening symptoms, poor fluid intake, or illness in someone with a weakened immune system.

Ask which precautions fit the person’s symptoms and health history, whether testing is useful, when close contact can resume, and which changes should trigger urgent assessment.