The rising number of cases has led to a slew of questions about the state of the COVID-19 pandemic, including what to do if you test positive for the virus.
The Centers for Disease Control and Prevention updated its guidance for how long people should quarantine or isolate after a possible exposure to COVID-19 or if they test positive for SARS-CoV-2.
In general, the CDC recommends people isolate for at least five days after they test positive. If after day five their symptoms are improving or they have remained asymptomatic, they can leave isolation and wear a mask around others, the CDC says.
Boosted and recently vaccinated people do not need to stay at home if they are possibly exposed to the coronavirus but should wear a mask for 10 days. People who are unvaccinated or have gone more than six months since receiving an mRNA vaccine or two months since the Johnson & Johnson vaccine should stay at home for at least five days and then wear a mask around others for five additional days, the CDC says.
But the new guidance has led some to criticize the CDC. Dr. Rochelle Walensky has said the guidelines come amid changing understanding of the virus's transmissibility and the rise in omicron cases. “We want to make sure there is a mechanism by which we can safely continue to keep society functioning while following the science,” she said Dec. 27.
In Michigan, the state health department said it wouldn't be following the relaxing guidelines, and the White House's top adviser on the coronavirus pandemic, Dr. Anthony Fauci, said the CDC was "very well aware" of the pushback. Fauci is head of the National Institute of Allergy and Infectious Diseases, separate from the CDC.
Here's what you need to know if you test positive for the coronavirus or if you were exposed to COVID-19:
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How long is someone contagious after they test positive for COVID-19?
The exact amount of time someone is contagious after a positive test can vary depending on a number of factors – such as whether they are symptomatic or how long after exposure they tested positive.
The CDC says most transmission of the coronavirus occurs within one to two days before the onset of symptoms and two to three days after.
In an appearance on "The Late Show with Stephen Colbert," Walensky said that 80% to 90% of a person's transmissibility is believed to occur within that five-day period before symptom onset and after.
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While that represents the majority of transmission, it may still be possible for someone to be contagious before or after or if they remain asymptomatic.
"We know that these tests can stay positive for a while,” Purvi Parikh, an allergist and immunologist with the Allergy and Asthma Network, told USA TODAY in December. “After 10 days, it's very unlikely you’ll be contagious.”
When is the best time to test for the coronavirus after symptoms start?
The CDC says that if you develop symptoms, get tested immediately and isolate until you receive the results.
If you do not develop symptoms, the CDC says, you should test at least five days after exposure. While testing before or after may still detect the presence of the coronavirus, five days after exposure is the optimal time, according to the CDC.
What is an antigen test? What is a PCR test?
Most self-tests are rapid antigen tests, which can detect the virus when a person is infectious and likely to pass it to others. The tests detect a viral protein on the surface of the coronavirus.
A negative antigen test, however, should be "presumptive" in most cases, the CDC says, and may require additional confirmation. Antigen tests work best when a person's viral load is highest, meaning a test early on in an infection or at a later stage may lead to a negative result, according to the CDC. If someone receives a negative antigen test early on an infection, they may be contagious later and would test positive.
Molecular PCR tests are more sensitive and can detect traces of the virus over a longer period during the course of an infection. They are part of a larger class of tests called nucleic acid amplification tests, or NAATs. Though some PCR tests can be performed at home, most are administered at clinics, doctors’ offices, hospitals or large-scale testing sites.
PCR tests and other NAATs may remain positive for weeks to months after an infection when a person is no longer contagious, according to the CDC. They remain the "gold standard" for diagnosis, the CDC says.
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What does a COVID-19 positive self-test result mean?
If someone tests positive for the coronavirus, regardless of vaccination status, the CDC says they should stay home and isolate for at least five days.
After five days, if that person remains asymptomatic or their symptoms are resolving, they can leave home if they wear a mask around others to reduce the risk of transmission, the CDC says.
CDC guidance before the late December update said people who were positive should isolate for 10 days starting on the first full day after developing symptoms. Asymptomatic people were told to isolate for 10 days after their positive test result under the old guidance.
If I test positive, how do I isolate?
Isolation is intended for people who have tested positive for the virus. People who isolate should stay at home and stay away from others inside their household. The CDC says a designated "sick room" and bathroom should be used for the infected person.
If I am possibly exposed to COVID-19, how do I quarantine?
Quarantine is different from isolation because it is intended for people who may have had an exposure to COVID-19, the CDC says.
If someone is exposed to COVID-19 but they are vaccinated and boosted, they do not need to remain at home for a quarantine period unless they develop symptoms, the CDC says. They should, however, wear a mask around others for 10 days.
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The CDC says people should remain at home for five days to quarantine if they are not vaccinated, they are not boosted, or it has been more than six months since receiving the Pfizer or Moderna shots or more than two months since the Johnson & Johnson shot.
After five days, they can leave home but should wear a mask around others. If they cannot quarantine, they should wear a mask around others for 10 days, the CDC says. If they develop symptoms at any point, they should stay at home.
All people, regardless of vaccination status, should also take a test at Day 5, if possible, after an exposure to the virus, the CDC says.
Am I free to leave quarantine after five days if I take a COVID-19 test?
The CDC guidance says you should wear a mask around others for 10 days if you've had a possible exposure.
While on "Colbert," Walensky addressed the question of how to interpret an antigen test five days after an exposure.
"If it's positive, stay home for another five days. If it's negative, I would say you still really need to wear a mask. You still may have some transmissibility ahead of you. You still should probably not visit Grandma. You shouldn't get on an airplane, and you should still be pretty careful when you're with other people by wearing a mask all the time."
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What over-the-counter medication can I take if I test positive for COVID-19?
Dr. Anita Gupta, adjunct assistant professor at the Johns Hopkins School of Medicine, told USA TODAY people who test positive for the coronavirus can take popular pain relief medication like acetaminophen or ibuprofen for aches and pains.
“That typically will lower the fever and help them just feel OK,” Gupta said.
But she noted that recommendations for pain relief medication may differ for children or older individuals. And over-the-counter medications won’t treat “the virus, but they’re just going to keep people generally comfortable.”
Gupta said people experiencing dry coughs can use cough medicine that contains dextromethorphan for some relief, while people with a productive cough may want to use medicine that contains guaifenesin. But cough medications shouldn’t be used for “a prolonged period of time.”
“If you’re going to manage COVID-19 at home, really the most important thing is to just get rest. Stay hydrated. These medications are not going to make COVID-19 go away faster,” Gupta said.
Additionally, over-the-counter vitamins have not been proven to treat or prevent COVID-19.
How long does it take to recover from COVID-19?
But millions of Americans have taken months to recover from COVID-19 or are still struggling with their illness. These “long-haulers” may face a wide range of symptoms, including breathlessness, brain fog, pain and more.
For millions, COVID-19 won’t quit: Doctors strive for answers on how to ease long-hauler misery.
What treatments are available for COVID-19?
The Food and Drug Administration last month authorized use of two antiviral medications, Pfizer’s Paxlovid and molnupiravir. Paxlovid can prevent nearly 90% of severe COVID-19 among those at high risk, and molnupiravir can prevent severe illness about 30% of the time.
Monoclonal antibodies, or drugs derived from people whose immune systems have fought off COVID-19, have helped people across the country at risk for severe symptoms from COVID-19, among other treatments.
But experts are warning that two widely used monoclonal antibodies are not likely to be effective against the spread of COVID-19's omicron variant. Some health care providers have been scrambling to get enough doses of a third monoclonal antibody treatment that appears to be effective against the variant.
New COVID treatments are coming: Will they help combat the omicron onslaught?
Contributing: Ken Alltucker and Adrianna Rodriguez, USA TODAY
This article originally appeared on USA TODAY: Positive COVID test? Guidelines for symptoms, self-tests, quarantine