Researchers estimate that people who get infected with the coronavirus can spread it to others 2 to 3 days before symptoms start and are most contagious 1 to 2 days before they feel sick.

When do you start being contagious with COVID-19?

A person with COVID-19 is considered infectious starting 2 days before they develop symptoms, or 2 days before the date of their positive test if they do not have symptoms.

Can an infected person spread COVID-19 before showing symptoms?

An infected person can spread COVID-19 starting 2 days before the person has any symptoms or tests positive. People who have COVID-19 don't always have obvious symptoms. A person is still considered a close contact even if they were wearing a mask while they were around someone with COVID-19.

How long does it take for symptoms of COVID-19 to appear after exposure?

Symptoms may appear 2 to 14 days after exposure to the virus.

Do COVID-19 and a common cold have a different incubation period?

While COVID-19 symptoms generally appear two to 14 days after exposure to SARS-CoV-2, symptoms of a common cold usually appear one to three days after exposure to a cold-causing virus.

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How long should I wait to get tested for COVID-19 after being exposed if I am fully vaccinated?

- If you have been fully vaccinated and around someone who has COVID-19 (close contact), you do not need to stay away from others (quarantine), or be restricted from work unless you develop COVID-like symptoms. We recommend that you get tested 3-5 days after your last exposure to someone with COVID-19.

What are some of the common symptoms of the COVID-19 disease?

Symptoms may include: fever or chills; cough; shortness of breath; fatigue; muscle and body aches; headache; new loss of taste or smell; sore throat; congestion or runny nose; nausea or vomiting; diarrhea.

What should you do if you have been around a person with COVID-19?

For Anyone Who Has Been Around a Person with COVID-19

Anyone who has had close contact with someone with COVID-19 should stay home for 14 days after their last exposure to that person.

What should I do if I've been exposed to a person with COVID-19 and I have fully recovered from a COVID-19 infection in the previous 90 days?

Someone who tested positive for COVID-19 with a viral test within the previous 90 days and has subsequently recovered and remains without COVID-19 symptoms does not need to quarantine. However, close contacts with prior COVID-19 infection in the previous 90 days should:
• Wear a mask indoors in public for 14 days after exposure.
• Monitor for COVID-19 symptoms and isolate immediately if symptoms develop.
• Consult with a healthcare professional for testing recommendations if new symptoms develop.

What is an asymptomatic case of COVID-19?

An asymptomatic case is an individual who has a laboratory confirmed positive test and who has no symptoms during the complete course of infection.

What is considered a close contact of someone with COVID-19?

For COVID-19, a close contact is anyone who was within 6 feet of an infected person for a total of 15 minutes or more over a 24-hour period (for example, three individual 5-minute exposures for a total of 15 minutes).

How long are you contagious if you are an asymptomatic carrier of COVID-19?

The Centers for Disease Control and Prevention recommends a 10- to 14-day quarantine period for anyone testing positive for the virus. The research from South Korea, however, found that asymptomatic people were contagious for about 17 days and those with symptoms were contagious for up to 20 days.

Should I be tested if I have been in close contact with someone who has COVID-19?

If you have been in close contact with someone who has COVID-19, you should be tested, even if you do not have symptoms of COVID-19. The health department may be able to provide resources for testing in your area.

Should I get tested after a close contact with someone who has COVID-19 if I am fully vaccinated?

• If you've had close contact with someone who has COVID-19, you should get tested 3-5 days after your exposure, even if you don't have symptoms. You should also wear a mask indoors in public for 14 days following exposure or until your test result is negative.

Am I considered a close contact for COVID-19 if I was wearing a mask?

A person is still considered a close contact even if they were wearing a mask while they were around someone with COVID-19. You can call, text, or email your contacts. By letting your close contacts know they may have been exposed to COVID-19, you are helping to protect everyone.

How long do you need to stay home after coming into close contact with someone who has COVID-19?

Anyone who has had close contact with someone with COVID-19 should stay home for 14 days after their last exposure to that person.

How long can long Covid last?

The medical community has been aware that while most people recover from COVID-19 within a matter of weeks, some will experience lingering symptoms for 4 or more weeks after developing COVID-19. Until now, there has not been a formal definition for this condition.

What are the most common symptoms for COVID-19 among those not hospitalized?

Fatigue, headache, and muscle aches (myalgia) are among the most commonly reported symptoms in people who are not hospitalized, and sore throat and nasal congestion or runny nose (rhinorrhea) also may be prominent symptoms.

What are some signs of COVID-19 that need immediate medical attention?

• Trouble breathing
• Persistent pain or pressure in the chest
• New confusion
• Inability to wake or stay awake
• Pale, gray, or blue-colored skin, lips, or nail beds, depending on skin tone

What steps should you take after coming into close contact with someone who tested positive for COVID-19?

• Stay home for 14 days after your last contact with a person who has COVID-19.
• Watch for fever (100.4◦F), cough, shortness of breath, or other symptoms of COVID-19.
• If possible, stay away from others, especially people who are at higher risk for getting very sick from COVID-19.

Can someone test negative and later test positive on a viral test for COVID-19?

Yes, it is possible. You may test negative if the sample was collected early in your infection and test positive later during this illness. You could also be exposed to COVID-19 after the test and get infected then. Even if you test negative, you still should take steps to protect yourself and others. See Testing for Current Infection for more information.

What should vaccinated people do if they come in contact with someone who has COVID-19?

Fully vaccinated people who have come into close contact with someone with COVID-19 should be tested 3-5 days following the date of their exposure and wear a mask in public indoor settings for 14 days or until they receive a negative test result. They should isolate if they test positive.

How long should I quarantine if I am COVID-19 asymptomatic?

If you continue to have no symptoms, you can be with others after 10 days have passed since you had a positive viral test for COVID-19.

How long will asymptomatic people test positive for COVID-19?

In general, asymptomatic people may test positive for 1-2 weeks, while those with mild-to moderate disease often continue to test positive for a week or more after this.

How long does isolation last for asymptomatic people during the COVID-19 pandemic?

For people who are infected but asymptomatic (never develop symptoms), isolation and precautions can be discontinued 10 days after the first positive test.