What to Do If You Were Exposed to COVID-19
If you have tested positive or are showing symptoms of COVID-19, isolate immediately.
About Being Exposed to COVID-19
A tool to help you determine if you need to isolate or take other steps to prevent spreading COVID-19.
If you were exposed to the virus that causes COVID-19 or have been told by a healthcare provider or public health authority that you were exposed, here are the steps that you should take, regardless of your vaccination status or if you have had a previous infection. Learn how COVID-19 spreads and the factors that make risk of spread higher or lower.
Wear a mask as soon as you find out you were exposed
Start counting from Day 1
- Day 0 is the day of your last exposure to someone with COVID-19
- Day 1 is the first full day after your last exposure
- Do not go places where you are unable to wear a mask. For travel guidance, see CDC’s Travel webpage.
Test even if you don’t develop symptoms.
If you already had COVID-19 within the past 90 days, see specific testing recommendations.
Continue taking precautions through day 10
- Wear a high-quality mask when around others at home and indoors in public
You can still develop COVID-19 up to 10 days after you have been exposed.
*About negative test results
As noted in the Food and Drug Administration labeling for authorized over-the-counter antigen tests, negative test results do not rule out SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions, including infection control decisions.
1Masks are not recommended for children under ages 2 years and younger, or for people with some disabilities. Other prevention actions (such as improving ventilation) should be used to avoid transmission during these 10 days.
Search for and find historical COVID-19 pages and files. Please note the content on these pages and files is no longer being updated and may be out of date.
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