Important update: Healthcare facilities

CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more

Find the latest information:
Aquatics FAQs
Recommendations for Fully Vaccinated People
COVID-19 Homepage

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.

UPDATE

Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

COVID-19 Testing: What You Need to Know

Updated Dec. 29, 2021

CDC has updated isolation and quarantine recommendations for the public, and is revising the CDC website to reflect these changes. These recommendations do not apply to healthcare personnel and do not supersede state, local, tribal, or territorial laws, rules, and regulations.

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Types of COVID-19 Tests

COVID-19 tests can detect either SARS-CoV-2, the virus that causes COVID-19, or antibodies that your body makes after getting COVID-19 or after getting vaccinated.

Tests for SARS-CoV-2 tell you if you have an infection at the time of the test. This type of test is called a “viral” test because it looks for viral infection. Antigen or Nucleic Acid Amplification Tests (NAATs) are viral tests.

Tests for antibodies may tell you if you have had a past infection with the virus that causes COVID-19. Your body creates antibodies after getting infected with SARS-CoV-2 or after getting vaccinated against COVID-19. These tests are called “antibody” or “serology” tests.

Testing is very important to help reduce the spread of COVID-19.

Viral Tests

A viral test tells you if you are infected with SARS-CoV-2, the virus that causes COVID-19. There are two types of viral tests: rapid tests and laboratory tests. Viral tests use samples that come from your nose or mouth. Rapid tests can be performed in minutes and can include antigen and some NAATs. Laboratory tests can take days to complete and include RT-PCR and other types of NAATs. Some test results may need confirmatory testing.

Self-tests are rapid tests that can be taken at home or anywhere, are easy to use, and produce rapid results. COVID-19 self-tests are one of many risk-reduction measures, along with vaccination, masking, and physical distancing, that protect you and others by reducing the chances of spreading COVID-19.

Antibody Tests

An antibody test (also known as a serology test) can detect antibodies to SARS-CoV-2 in your blood. Antibodies are proteins that your immune system makes to help fight infection and protect you from getting sick in the future.

Antibody tests should not be used to diagnose a current infection, but may indicate if you had a past infection. Antibody tests help scientists learn about how human immune systems defend against the virus, as well as learn about population-level protection.

Antibody testing is not currently recommended to determine: