How long can someone with COVID-19 be contagious?

Available data suggest that patients with mild-to-moderate COVID-19 remain infectious no longer than 10 days after symptom onset.

How long after you test positive for COVID-19 are you contagious?

"A person with COVID-19 is considered infectious starting two days before they develop symptoms, or two days before the date of their positive test if they do not have symptoms," according to the CDC. Regardless of symptoms, those who test positive are advised to take specific precautions for at least 10 days.

How long should I stay in home isolation if I have a COVID-19 infection?

Positive. The test detected the virus and you have an infection. Stay home for at least 5 days and isolate from others in your home.

Tell your close contacts. Wear a well-fitted mask when around others. If available, a N95 or KN95 respirator is recommended. Watch for symptoms.

How long could COVID-19 usually linger in your body?

But for most infected people, virus levels in the body peak between three and six days after the original infection, and the immune system clears the pathogen within 10 days. The virus shed after this period is generally not infectious.

Are recovered persons with persistent positive test of COVID-19 infectious to others?

Persons who have tested persistently or recurrently positive for SARS-CoV-2 RNA have, in some cases, had their signs and symptoms of COVID-19 improve. When viral isolation in tissue culture has been attempted in such persons in South Korea and the United States, live virus has not been isolated. There is no evidence to date that clinically recovered persons with persistent or recurrent detection of viral RNA have transmitted SARS-CoV-2 to others.

Despite these observations, it’s not possible to conclude that all persons with persistent or recurrent detection of SARS-CoV-2 RNA are no longer infectious. There is no firm evidence that the antibodies that develop in response to SARS-CoV-2 infection are protective. If these antibodies are protective, it’s not known what antibody levels are needed to protect against reinfection.

Omicron variant has shorter incubation period, nearly 20 times more contagious than other strains

Can patients who have recovered from COVID-19 continue to have detectable SARS-CoV-2 RNA in upper respiratory specimens?

• Patients who have recovered from COVID-19 can continue to have detectable SARS-CoV-2 RNA in upper respiratory specimens for up to 3 months after illness onset in concentrations considerably lower than during illness; however, replication-competent virus has not been reliably recovered and infectiousness is unlikely.

Why might someone continue to test positive for COVID-19 after isolation?

According to Benjamin tenOever, a microbiologist at the NYU Grossman School of Medicine, some people may continue to test positive because the weakened virus keeps replicating, or because of broken virus genomes.

How long after COVID-19 isolation should I wear a mask?

During the 10 days after infection, persons might be infectious to others and are recommended to wear a well-fitting mask when around others, and to avoid contact with those at elevated risk for severe disease, even if ending isolation after 5 days.

How long does isolation take after COVID-19 infection if you were severely ill or have a weakened immune system?

CDC recommends an isolation period of at least 10 and up to 20 days for people who were severely ill with COVID-19 and for people with weakened immune systems. Consult with your healthcare provider about when you can resume being around other people.

How long should I quarantine after COVID-19 exposure if I am vaccinated?

Quarantine: If you have received all vaccine and booster doses recommended by CDC, you do not need to quarantine. You should wear a well-fitting mask around others for 10 days from the date of your last close contact with someone with COVID-19 (the date of last close contact is considered day 0).

What is the incubation period for COVID-19?

People with COVID-19 have reported a wide range of issues from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus.

What is the incubation period of the COVID-19 variant?

Omicron is now the most dominant strain of coronavirus in the U.S., and its incubation period may be shorter than those of previous variants. Research is just beginning. But some scientists who've studied Omicron and doctors who've treated patients with it suggest the right number might be around 3 days.

What should I do if I test positive for COVID-19?

Stay home for at least 5 days and isolate from others in your home.

Tell your close contacts.

Wear a well-fitting mask when around others. If available, a N95 or KN95 respirator is recommended.

Watch for symptoms.If you have any emergency warning signs, seek emergency care immediately.

Tell your healthcare provider.

How long are immunocompromised people contagious during the COVID-19 pandemic?

Some severely immunocompromised persons with COVID-19 may remain infectious beyond 20 days after their symptoms began and require additional SARS-CoV-2 testing and consultation with infectious diseases specialists and infection control experts.

How long does it usually take for your body to build up immunity after having a full specific COVID-19 vaccination scheme?

It takes a couple of weeks for your body to build immunity after vaccination.

What is the recovery time for COVID-19 patients with Acute Respiratory Distress Syndrome (ARDS)?

Most people who survive ARDS go on to recover their normal or close to normal lung function within six months to a year. Others may not do as well, particularly if their illness was caused by severe lung damage or their treatment entailed long-term use of a ventilator.

Should I wear a mask after a COVID-19 isolation in the US?

Yes. After the end of the 5-day quarantine or isolation period, continue to wear a well-fitting mask around others at home and in public for 5 additional days (day 6 through day 10). If you are unable to wear a mask when around others, you should continue to isolate for 10 days. Avoid people who are immunocompromised or at high risk for severe disease, and nursing homes and other high-risk settings, until after at least 10 days. Do not go to places where you are unable to wear a mask, such as restaurants, bars, and some gyms, until 10 days after the start of quarantine or isolation.

Can I remove my mask in public places after the end of isolation/quarantine for COVID-19?

No. After your 5 days of quarantine or isolation end, you should continue to wear a well-fitting mask when around others at home and in public for 5 days. Refer to current CDC guidance for mask wear to determine what to do after the 10-day period is complete.

Can I stop wearing a face mask and social distancing after receiving the COVID-19 vaccine?

Not yet. We don’t know how effective the vaccine is going to be, or how many people are going to receive it. The recommendation is continue to practice social distancing, wear a face mask, and really good hand-washing. We’re going to have to do this for a little while longer.

Should I isolate and get tested if I have recovered from COVID-19 but I have symptoms again?

If a previously infected person experiences new symptoms consistent with COVID-19 3 months or more after the date of the previous illness onset (or date of last positive viral diagnostic test [RT-PCR or antigen test] if the person never experienced symptoms), the person should undergo repeat viral diagnostic testing. However, serologic testing should not be used to establish the presence or absence of SARS-COV-2 infection or reinfection. These people who have a positive test result should be considered infectious and remain isolated until they again meet criteria for discontinuation of isolation or of transmission-based precautions. Contact tracing during the person’s second episode of symptoms is warranted.

Should you get the COVID-19 vaccine if you already had COVID-19 and recovered?

If I already had COVID-19 and recovered, do I still need to get a COVID-19 vaccine? You should get a COVID-19 vaccine even if you already had COVID-19. Getting a COVID-19 vaccine after you recover from COVID-19 infection provides added protection to your immune system.

How long after infection with the virus that causes COVID-19 can the antibody test be effective?

After infection with the COVID-19 virus, it can take two to three weeks to develop enough antibodies to be detected in an antibody test, so it's important that you're not tested too soon.

Will a person with COVID-19 vaccine have a positive antibody test?

A COVID-19 vaccination may also cause a positive antibody test result for some but not all antibody tests. You should not interpret the results of your SARS-CoV-2 antibody test as an indication of a specific level of immunity or protection from SARS-CoV-2 infection.

What is the difference between SARS-CoV-2 and COVID-19?

In 2019, a new coronavirus was identified as the cause of a disease outbreak that originated in China. The virus is now known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease it causes is called coronavirus disease 2019 (COVID-19).

How long should I stay in home isolation if I have a COVID-19 infection?

Positive. The test detected the virus and you have an infection. Stay home for at least 5 days and isolate from others in your home.

Tell your close contacts. Wear a well-fitted mask when around others. If available, a N95 or KN95 respirator is recommended. Watch for symptoms.