Getting exposed to COVID-19 can be scary. You may worry about getting sick or infecting others. Fortunately, with the right precautions, you can help prevent the spread of COVID-19 after an exposure.
What counts as COVID exposure?
According to the CDC, exposure to COVID-19 occurs when you have close contact with someone who has tested positive for COVID-19. Close contact includes:
- Being within 6 feet of someone with COVID-19 for 15 minutes or more over a 24-hour period
- Providing care to someone who is sick with COVID-19
- Having direct physical contact with someone who has COVID-19 (like hugging or kissing)
- Sharing eating or drinking utensils with someone who has COVID-19
- Being sneezed or coughed on by someone with COVID-19
You are considered exposed even if the person with COVID-19 had no symptoms. The exposure window starts 2 days before the person developed COVID-19 symptoms or tested positive.
How long does it take to develop COVID-19 after exposure?
If you’ve been exposed to COVID-19, it can take anywhere from 2 to 14 days to develop the illness. This is called the incubation period. Most people will develop symptoms around 5 days after exposure, but every case is different.
Median COVID-19 incubation period
Days from exposure to symptom onset | Percentage of cases |
---|---|
2 days | 2.5% |
3 days | 8.2% |
4 days | 15.6% |
5 days | 22.3% |
6 days | 16.6% |
7 days | 10.7% |
8 to 14 days | 24.1% |
As shown in the table, most people develop COVID-19 symptoms within 4 to 6 days after exposure. However, it’s possible to develop symptoms anywhere from 2 to 14 days after exposure, so it’s important to isolate for the full 14 days.
How long should you isolate after COVID-19 exposure?
The CDC recommends quarantining for 14 days after COVID-19 exposure. This reduces the risk of spreading the virus to others if you become infected.
Here are the CDC guidelines for quarantine after exposure:
- Stay home and avoid contact with others for 14 days from the date of last exposure.
- Monitor your health for fever, cough, shortness of breath, or other COVID-19 symptoms during the 14 days.
- Maintain physical distance of at least 6 feet from others.
- Wear a well-fitted mask if you must be around others in your home.
- Do not travel during the 14 days.
- Get tested for COVID-19 at least 5 days after exposure or if you develop symptoms.
- Quarantine for 14 days even if you test negative for COVID-19.
You should quarantine for the full 14 days even if you don’t have any symptoms during that timeframe. Some people infected with COVID-19 are asymptomatic but can still transmit the virus.
Can quarantine be shortened after COVID exposure?
In some circumstances, the recommended quarantine period can be shortened to 10 or 7 days after exposure. However, there are specific criteria required to end quarantine early:
10-day quarantine (no testing)
- No symptoms developed during the 10-day period.
- Continue monitoring symptoms and mask-wearing for 14 days total.
7-day quarantine (with negative test)
- Get tested on day 5 or later after exposure.
- No symptoms developed during the 7-day period.
- Test result is negative.
- Continue monitoring symptoms and mask-wearing for 14 days total.
Shortening quarantine carries some additional risk of spreading COVID-19. The 14-day quarantine period remains the safest option to prevent transmission.
How long are you contagious after COVID exposure?
If you develop COVID-19 after an exposure, you can spread the infection to others for up to 10 days after symptoms first appeared. However, you are generally most contagious 1-2 days before symptoms start and 2-3 days after.
This timeline varies for people who don’t have symptoms. According to the CDC:
- Asymptomatic cases can transmit COVID-19 up to 10 days after they tested positive.
- People with mild to moderate illness who are contagious can transmit for up to 10 days after symptoms began.
- People with severe COVID-19 illness could be contagious for up to 20 days after symptoms began.
That’s why it’s critical to isolate for at least 10 days after COVID-19 exposure or a positive test. Wearing a well-fitted mask also reduces viral spread when around others.
How long before a COVID test is accurate after exposure?
If you’ve been exposed to COVID-19, a test won’t be accurate right away. There is an incubation period before the virus replicates enough to be detected. For accurate results, the CDC recommends:
- Get tested at least 5 days after exposure.
- If symptoms develop, get tested immediately.
- Negative results before 5 days could be false negatives so continue quarantining for 14 days.
Molecular tests that detect viral RNA, such as RT-PCR tests, are most accurate in the early stages of infection. Rapid antigen tests produce more false negative results and may not detect COVID-19 until 3-5 days after exposure.
Can you test negative and still have COVID after exposure?
Yes, it’s absolutely possible to be exposed to COVID-19, get infected, and still test negative – especially within the first 5 days. Reasons include:
- Testing too early before viral levels are detectable
- Improper sample collection leading to false negative
- The test itself is not 100% accurate
According to research, the false negative rate for COVID-19 tests ranges from 2% to 37%. To protect yourself and others, isolate for the full 14 days even if you test negative within the first week after exposure.
Likelihood of false negative result by days since exposure
Days since exposure | False negative rate |
---|---|
1 day | 100% |
2 days | 40% |
3 days | 20% |
4 days | 10% |
5+ days | 5% |
As shown, false negative rates start out very high after exposure but become much lower 5 days or more after exposure. This demonstrates the importance of ideal timing for accurate test results.
What precautions should you take after COVID exposure?
To protect yourself and others after COVID exposure, the CDC recommends:
- Quarantine for 14 days from last exposure.
- Watch for COVID-19 symptoms like fever, cough, fatigue.
- Consider getting tested at least 5 days after exposure.
- Wear a high-quality mask or respirator when around others at home.
- Practice social distancing and good hygiene.
- Clean and disinfect high-touch surfaces regularly.
- Improve ventilation and airflow when possible.
Even if you don’t develop symptoms, continue precautions like masking and distancing for the full 14 days. This helps prevent asymptomatic transmission of COVID-19.
What should you do if COVID symptoms develop after exposure?
If you develop COVID-19 symptoms like fever, cough, or shortness of breath during quarantine, take the following steps:
- Isolate immediately in a separate room away from others in your home.
- Wear a high-quality mask if you must be around others.
- Get tested for COVID-19 right away.
- Monitor your symptoms and seek medical care if they worsen.
- Inform close contacts you had before symptoms that they were exposed.
- End isolation only after 10 days since symptoms started and 24 hours fever-free.
Let your doctor know you were exposed to COVID-19 prior to symptom onset. Seek immediate medical attention for any severe or concerning symptoms like difficulty breathing, chest pain, or bluish lips or face.
Does COVID exposure make you immune if you don’t get sick?
Unfortunately, COVID-19 exposure does not guarantee future immunity if you don’t get infected. Early research showed antibodies developing after exposure, even without symptoms. However, more recent studies have cast doubt on this idea.
For example, a 2022 study in JAMA Network Open found no difference in antibody levels between people with asymptomatic exposure compared to those never exposed. This suggests exposure alone may not provide robust, durable protection against future infection.
Getting vaccinated is still the best way to build immunity, even after exposure. COVID-19 vaccination helps prevent both initial infection and severe disease if exposed again.
Can you get COVID twice after exposure?
Yes, it’s possible to get COVID-19 more than once, even after a known exposure. Reinfection can occur due to:
- The initial exposure did not result in infection and immunity.
- Waning immunity over time after an initial infection.
- Exposure to a new COVID variant able to evade immune defenses.
In general, reinfections tend to be milder compared to the initial infection thanks to some lingering immunity. But severe disease can still happen, especially for high-risk groups. Using precautions after exposure helps prevent both first infections and reinfections.
Conclusion
Getting exposed to COVID-19 can be worrisome, but understanding isolation timelines helps reduce transmission risk. The CDC recommends quarantining for 14 days after exposure due to the incubation period of the virus.
Isolating for just 10 days or 7 days with a negative test result are also acceptable alternatives. However, the full 14 days remains the safest option for preventing spread from a possible COVID-19 infection.
Be alert for any COVID symptoms during the 14 days after exposure. Seek testing if symptoms occur. And even if you stay symptom-free or test negative, continue precautions like masking, distancing, and handwashing though the entire quarantine period.