Omicron Has Slightly Different Symptoms from Previous COVID Variants — Here's What to Know

Omicron is sweeping the globe, with the highly contagious new variant leading to record-breaking numbers of infections, including a whopping 1,018,935 in the U.S. alone on Monday.

And for those infected, they're noticing symptoms that are slightly different from what we had learned over the last two years about COVID-19. This time around, the shortness of breath and loss of taste and smell that characterized the earlier strains of the virus seem to be absent, replaced by milder, cold-like symptoms.

As more people get infected, here's what to look out for with omicron.

What are the symptoms?

The omicron variant was first identified in November because a doctor in South Africa noticed that she had a patient who tested positive for COVID-19, but had slightly different symptoms from past cases.

"It actually started with a male patient who's around the age of 33 ... and he said to me that he's just [been] extremely tired for the past few days and he's got these body aches and pains with a bit of a headache," Dr. Angelique Coetzee told the BBC, adding that he had a "scratchy throat" and never lost his sense of taste or smell.

That is in line with what omicron patients have reported in the months since. A large study in South Africa of 78,000 omicron patients found that they were most likely to experience a runny nose, sore throat, fatigue, headache and a minor cough, if any at all. Some people also reported experiencing lower back pain along with muscle aches.

Unlike the delta variant or other previous versions of COVID-19, omicron patients were less likely to have a fever, shortness of breath that required supplemental oxygen and few lost their sense of taste or smell.

How soon do people get infected?

Part of the reason why omicron is spreading so quickly is because it appears to have a shorter incubation period, Dr. Waleed Javaid, the director of infection prevention and control at Mount Sinai Downtown told The New York Times.

Rather than the four to six days it took for symptoms to appear with delta, many omicron patients are getting sick and testing positive within three days. Javaid said that omicron's many mutations likely makes it easier for the variant to go inside cells and infect people.

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Is omicron milder?

Omicron does appear to produce a milder illness than previous variants, but mostly in people who are fully vaccinated and boosted.

On Tuesday, the World Health Organization said that more evidence is pointing to omicron as an upper respiratory infection that is less likely to lead to severe illnesses or death.

"We are seeing more and more studies pointing out that omicron is infecting the upper part of the body. Unlike other ones, the lungs who would be causing severe pneumonia," WHO Incident Manager Abdi Mahamud said.

Still, the protection of a COVID-19 vaccine and a booster is vital to reducing the risk of hospitalization or death.

"There are people who get severe illness from omicron," Javaid told the Times. "It is still a coronavirus. We're still in a pandemic."

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