Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
UPDATE
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.

What to Do If You Were Exposed to COVID-19

What to Do If You Were Exposed to COVID-19
Updated Aug. 24, 2022

If you have tested positive or are showing symptoms of COVID-19, isolate immediately.

About Being Exposed to COVID-19

Isolation and Exposure Calculator

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.

After Being Exposed to COVID-19

START PRECAUTIONS
Immediately

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
CONTINUE PRECAUTIONS
10 Full Days
You can still develop COVID-19 up to 10 days after you have been exposed
Take Precautions

Wear a high-quality mask or respirator (e.g., N95) any time you are around others inside your home or indoors in public 1

  • Do not go places where you are unable to wear a mask. For travel guidance, see CDC’s Travel webpage.

Take extra precautions if you will be around people who are more likely to get very sick from COVID-19.

More about how to protect yourself and others

Watch for symptoms

If you develop symptoms

If your test result is positive, follow the isolation recommendations.

GET TESTED
Day 6
Get tested at least 5 full days after your last exposure

Test even if you don’t develop symptoms.

If you already had COVID-19 within the past 90 days, see specific testing recommendations.

IF YOU TEST
Negative

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.

IF YOU TEST
Positive

Isolate immediately

*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.

Archived Content

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.

  • Visit archive.cdc.gov for a historical snapshot of the COVID-19 website, capturing the end of the Federal Public Health Emergency on June 28, 2023.
  • Visit the dynamic COVID-19 collection to search the COVID-19 website as far back as July 30, 2021.