As cases of the coronavirus surge with the new omicron variant continuing to spread following the holidays, your chances of being exposed to someone with the virus have likely increased. But when might symptoms first appear following a potential exposure?
Some experts say the omicron variant has "sped up" timing for what many have come to know with COVID, including the incubation period, or the time between exposure and the start of symptoms. But while it's taking less time to develop symptoms, for many people it is also taking less time to recover.
Changes sparked by the variant have resulted in new guidance from the Centers for Disease Control and Prevention, which shifted the timing for isolation and quarantine.
Here's what we know so far.
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How Soon Might COVID Symptoms Appear?
According to earlier CDC guidance, COVID symptoms can appear anywhere from two to 14 days after someone is exposed to the virus.
Anyone exhibiting symptoms should get tested for COVID-19.
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Some people may never experience symptoms, though they can still spread the virus.
A person is also considered contagious before symptoms appear.
When Are People with COVID Most Contagious?
The CDC says that its guidelines were updated to reflect growing evidence that suggests transmission of COVID-19 often occurs one to two days before the onset of symptoms and during the two to three days afterward.
For those without symptoms, CDC guidance states they are considered contagious at least two days before their positive test.
When is the Best Time to Get Tested After Exposure?
The CDC states that anyone who may have been exposed to someone with COVID should test five days after their exposure, or as soon as symptoms occur.
"If symptoms occur, individuals should immediately quarantine until a negative test confirms symptoms are not attributable to COVID-19," the guidance states.
Health experts say that while incubation times could be changing, those who test early should continue testing even if they get negative results.
How Long Should you Quarantine or Isolate?
First things first, those who believe they have been in contact with someone who has COVID and are unvaccinated should quarantine. Those who test positive, regardless of vaccination status, must isolate, according to the Centers for Disease Control and Prevention.
Here's the difference between the two:
Those who have been within six feet of someone with COVID for a cumulative total of at least 15 minutes over a 24-hour period should quarantine for five days if unvaccinated, or if they are more than six months out from their second vaccine dose, according to updated CDC guidance issued Monday.
Once that period ends, they should partake in strict mask use for an additional five days.
Previously, the CDC said people who were not fully vaccinated and who came in close contact with an infected person should stay home for at least 10 days.
Prior to Monday, people who were fully vaccinated — which the CDC has defined as having two doses of the Pfizer or Moderna vaccines, or one dose of the Johnson & Johnson vaccine — could be exempt from quarantine.
Those who are both fully vaccinated and boosted do not need to quarantine if they are a close contact of someone with COVID, but should wear a mask for at least 10 days after exposure. The same goes for those who are fully vaccinated and not yet eligible for their booster shot.
People who are positive for COVID should stay home for five days, the CDC said Monday, changing guidance from the previously recommended 10 days.
At the end of the period, if you have no symptoms, you can return to normal activities but must wear a mask everywhere — even at home around others — for at least five more days.
If you still have symptoms after isolating for five days, stay home until you feel better and then start your five days of wearing a mask at all times.
So how do you calculate your isolation period?
According to the CDC, "day 0 is your first day of symptoms." That means that Day 1 is the first full day after your symptoms developed.
For those who test positive for COVID but have no symptoms, day 0 is the day of the positive test. Those who develop symptoms after testing positive must start their calculations over, however, with day 0 then becoming the first day of symptoms.
When Should You Call a Doctor?
The CDC urges those who have or may have COVID-19 to watch for emergency warning signs and seek medical care immediately if they experience symptoms including:
- 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
"This list is not all possible symptoms," the CDC states. "Please call your medical provider for any other symptoms that are severe or concerning to you."
You can also notify the operator that you believe you or someone you are caring for has COVID.