When you have COVID-19, you are generally contagious from about 2 days before symptoms start (or before a positive test if asymptomatic) and remain contagious for an average of 8 to 10 days after symptoms begin. The infectious period can vary depending on the severity of illness and individual factors. People with mild to moderate symptoms are usually contagious for up to 10 days, while those severely ill or immunocompromised may be infectious for longer, up to 20 days. It is recommended to isolate for at least 5 days and continue precautions like mask-wearing for an additional 5 days. You are considered less contagious if you have no fever for 24 hours and your symptoms have improved, but it is still wise to take precautions especially around high-risk individuals during the full infectious period.
Key points about contagiousness:
- Contagious period starts about 48 hours before symptoms or positive test.
- Usually contagious for 8 to 10 days on average.
- Severe or immunocompromised cases may be contagious longer (up to 20 days).
- Isolation typically recommended for 5 days, with mask use for 5 more days.
- Symptoms improving and being fever-free for 24 hours is a sign you are less contagious.
- Rapid antigen tests can help confirm if still contagious but are not 100% accurate.
This timeline helps to reduce spreading the virus to others and protect vulnerable populations.