COVID-19 infectious period: what to know

People can spread COVID-19 before they realise they are ill, and the chance of transmission is often greatest around the beginning of symptoms. Infectiousness generally decreases as recovery progresses, but a positive test, ongoing symptoms, or a weakened immune system can mean extra caution is sensible. A cough may continue after the period of greatest infectiousness, so cough alone does not establish how contagious someone is. COVID-19 can cause fever, headache, fatigue, or a general feeling of being unwell.

Stay home when unwell and follow current local public-health advice about returning to normal activities. Improve airflow, avoid close contact with people at higher risk, and consider a well-fitting mask around others when infection is possible. Do not share drinks or personal items, and wash hands after coughing or blowing your nose. Tell close contacts if you receive a positive result so they can make informed decisions. A clinician can advise if symptoms persist or recovery is not progressing.

Get urgent help for severe breathing difficulty, persistent chest pain, fainting, blue or grey lips, or unusual difficulty staying awake. Contact a clinician promptly for worsening symptoms, dehydration, confusion, or a return of fever after improvement. COVID-19 can sometimes lead to pneumonia, and symptoms that are worsening rather than settling deserve assessment.

Ask when you can safely resume close contact, whether your symptoms or health conditions alter precautions, and what to do if a test remains positive while you feel better.