When Should You Get Tested for COVID-19 After Being Exposed?

An illustration of a rapid COVID test with a test tube and a swab on a light blue background.


Key Takeaways

  • The Centers for Disease Control and Prevention (CDC) recommends that vaccinated people get tested between five and seven days after a known or suspected exposure to COVID-19. People who are unvaccinated should get tested immediately after being exposed to the virus. 
  • It's important to get tested if you've been exposed—even if you don't feel sick—as studies have suggested that up to 59% of COVID transmission comes from people who are asymptomatic.
  • Experts recommend both rapid antigen and PCR tests, but encourage people to get tested with whichever test is most accessible and convenient to them.

With the holidays fast approaching, COVID-19 safety planning is probably on your mind if you're planning get-togethers with family and friends. However, these gatherings can serve as hot spots for the virus to spread.

To help curb the spread of the virus at any time of year—but especially headed into the holiday season—experts want to make sure that people know the current guidelines for COVID testing.

Here's what you need to know about getting tested for COVID, including how the guidelines differ depending on your vaccination status.

When Should I Test?

The guidelines for testing change as scientists learn more about the COVID virus, but as of the beginning of November 2021, the Centers for Disease Control and Prevention (CDC) recommends that people get tested after a known or suspected exposure. However, the timing of the test will depend on whether a person is vaccinated or not.

After being exposed, the earliest that a person can test positive for COVID is between 24 and 48 hours. 

If you're vaccinated, the CDC recommends getting tested between five and seven days after you came into contact with a person that may have or has confirmed COVID.

Jeffrey Klausner, MD, board-certified internist, infectious disease specialist, and Curative Independent Medical Director, tells Verywell that providers generally wait to test "at least 48 to 72 hours" after a patient has had a known exposure because "it takes a bit of time for the virus to reach a point of detection" after someone has been exposed to the virus.

If you're unvaccinated, the CDC recommends testing immediately after a known exposure.

Klausner says that someone who is unvaccinated and has had a known exposure to COVID "should quarantine, avoid contact with others, and consistently wear a mask so they do not spread infections to others until they obtain their test result."

Why Testing Still Matters

Even though the current COVID-19 vaccines are highly effective, testing is still the strongest way to find out who is infected—especially when people do not have symptoms but could still potentially spread the virus to others.

Research has suggested that around 59% of COVID-19 transmission is asymptomatic, with 35% coming from presymptomatic people (before they feel sick) and 24% from people who never develop symptoms.

Which Test Should I Use? 

Greg Schrank, MD, MPH, assistant professor of medicine at the University of Maryland School of Medicine and hospital epidemiologist at the University of Maryland Medical Center, tells Verywell that rapid antigen tests and PCR lab tests can both be used to detect COVID-19 infection, but there are pros and cons of each to consider.

“PCR tests are able to detect even very low quantities of virus and have a higher sensitivity as compared to rapid tests," says Schrank. However, “they have the disadvantage of taking longer—in some cases up to a few days to result.” 

Rapid antigen tests are faster and easy to administer, allowing people to get results back as soon as the same day. Robert G. Lahita, MD, PhD, director of the Institute for Autoimmune and Rheumatic Disease at Saint Joseph Health, tells Verywell that a rapid test "can be done within minutes of exposure." However, a caveat is that these tests may not detect low levels of the virus, as a PCR test can.

Rapid tests and PCR tests are both useful but each has its pros and cons. If you've been exposed to COVID or have symptoms, the best test to use is the one that you can access as soon as possible.

“Both types of tests are useful, and I would encourage individuals who are testing because of symptoms or an exposure to use the test most quickly available to them," Schrank says.

If someone tested negative for COVID-19 despite having COVID-19 symptoms, Schrank recommends a second antigen test 24 to 36 hours later and a PCR test as a follow-up. 

Tips for Navigating the Holidays 

If you're planning on gathering indoors for the holidays, Klausner says that there are steps that you can take to help keep your loved ones safe. He recommends ventilating your spaces by opening windows, wearing masks, and getting vaccinated.

Vaccination remains the safest and best way to protect yourself and others," says Klausner. "Nearly four out of five Americans have at least one dose."

Schrank says that “the safest way to enjoy the holidays together with friends and family is for everyone who is eligible to be fully vaccinated." Importantly, he says it's "best way to protect young children who are not yet eligible [for vaccination] or more vulnerable adults like the elderly or immunocompromised that remain at higher risk even after vaccination.” 

What This Means For You

If you are exposed to someone who has COVID or may have COVID, you will need to get tested. If you are vaccinated, you should get tested 5 to 7 days after you were exposed. If you're unvaccinated, you should get tested right away as soon as you learn that you were exposed.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Overview of Testing for SARS-CoV-2.

  2. Johansson MA, Quandelacy TM, Kada S, et al. SARS-CoV-2 Transmission From People Without COVID-19 Symptoms. [published correction appears in JAMA Netw Open. 2021 Feb 1;4(2):e211383]. JAMA Netw Open. 2021;4(1):e2035057. Published 2021 Jan 4. doi:10.1001/jamanetworkopen.2020.35057

By Kayla Hui, MPH
Kayla Hui, MPH is the health and wellness ecommerce writer at Verywell Health.She earned her master's degree in public health from the Boston University School of Public Health and BA from the University of Wisconsin-Madison.