Can omicron cause long COVID-19?

By mid-January, close to 99% of all new COVID-19 cases in the U.S. were due to the omicron variant. Since then, case numbers have continued to soar and hospitals across the country now find themselves overwhelmed by people with COVID-19 seeking care.

Early reports have indicated that the omicron variant is different than other variants of the coronavirus. It was labeled a variant of concern by the World Health Organization (WHO) because of the number of mutations within it — 22 more than the delta variant. And while omicron spreads like no other previous variant, it is believed that it may lead to milder illness.

However, questions about the symptoms of COVID-19 caused by omicron remain: Are the symptoms different, or just milder? Can the symptoms last after the infection and even be long-term — known as long-haul COVID-19 or long COVID?

According to Dr. Kaveh Bahmanpour, a board-certified family medicine and geriatric medicine doctor affiliated with Sharp Community Medical Group, some of the answers to these questions about omicron have been revealed and some are still unknown.

“It has become apparent that omicron generally leads to milder symptoms for the most part,” Dr. Bahmanpour says. “And symptoms usually last 5 to 10 days, which is shorter than previous variants, which could last up to 14 days.”

The Centers for Disease Control and Prevention (CDC) does not differentiate between the symptoms caused by each variant. Common symptoms of COVID-19 — regardless of which variant may have caused the infection — include the following, with the symptoms in bold being the most reported now:

• Cough

• Congestion or runny nose

• Fatigue

• Headache

• Sore throat

• Muscle or body aches

• Shortness of breath or difficulty breathing

• New loss of taste or smell

• Fever or chills

• Nausea or vomiting

• Diarrhea

The possibility of long COVID
While omicron may cause less severe symptoms, this may not mean a decreased risk of long-term sickness. In fact, the CDC advises that long COVID — a range of symptoms that can last weeks or months after a person is first infected, or can appear weeks after infection — can happen to anyone who has had COVID-19, even if their illness was mild or they didn’t have any symptoms (asymptomatic).

Experts estimate up to 30% of people who have experienced COVID-19 are likely to have persistent symptoms. These symptoms can include those commonly experienced with COVID-19, along with:

• Brain fog

• Chest or stomach pain

• Lightheadedness

• Fast-beating or pounding heart (heart palpitations)

• Sleep problems

• Change in smell or taste

• Sensation of pins and needles

• Rash

• Mood changes

Also, a small number of children with COVID-19 — or who had COVID-19 — experience multisystem inflammatory syndrome (MIS-C). MIS-C is a rare, life-threatening condition that can cause dangerous inflammation in the eyes, skin, blood vessels and heart.

“The possibility of long-term symptoms was something that we found out later in the course of the disease,” Dr. Bahmanpour says. “As we collect more data about each variant, we will be able to predict more. For now, while omicron seems to cause milder symptoms, the possibility of long-term effects is something yet to be determined.”

Decrease your risk
Hospitals across San Diego County are experiencing a surge of patients with severe COVID-19 due to the increased contagiousness of omicron, indicating that not all omicron-related cases are mild. In California alone, the average daily number of patients hospitalized with COVID-19 in the first two weeks of the year was over 11,000.

What’s more, unvaccinated people in the state were found to be eight times more likely to be hospitalized with COVID-19 than fully vaccinated people. This is why vaccination — and receiving a booster shot when eligible — remains vital to stop the spread of COVID-19 and reduce the risk of severe illness, hospitalization and death.

If you experience a coronavirus infection, regardless of your vaccination status, Dr. Bahmanpour advises following the CDC guidance to isolate for no less than 5 days from when symptoms started or testing positive. Isolation can end only if you are fever-free for 24 hours without the use of fever-reducing medication and any other symptoms are improving. You should then wear a face mask around others — in your home and in public — for 5 more days.

“Most of the symptoms should improve after 10 days,” he says. “However, if you are still feeling fatigue and headache or persistent cough, you should be seen by a doctor. Additionally, if you experience shortness of breath anytime during the course of the disease, you need to seek immediate care.”

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