Can Omicron cause long COVID?

According to Centers for Disease Control and Prevention (CDC), long COVID, also called chronic or long-haul COVID, is a range of more than 50 symptoms that can last weeks or months after a person has been infected with COVID-19.

There was no apparent difference in symptoms between acute COVID-19 infections caused by Omicron and those caused by other variants such as Delta.

The main symptoms of Omicron infections, according to a ZOE study, are:

• runny nose
• headache
• tired
• sneeze
• sore throat

“Although there are indications that the Omicron variant spreads more easily, fortunately early data suggests that the variant may cause less severe disease in the population,” said Dr Scott Lillibridge, physician, epidemiologist and director of emergency response for International Medical Corps.

Even though so far the majority of the population experiences milder and milder symptoms with Omicron, this could be due to a higher level of immunity (via infection or vaccines) in the population, the experts point out.

“[M]all Omicron infections in the United States are breakthrough infections [infections in vaccinated persons] since the majority of the population is fully vaccinated. A less severe course is expected in a vaccinated person,” said Dr. Marisa Montecalvo, professor of medicine and medical director of NYMC Health Services at New York Medical College.

A study of COVID symptoms in the UK found those vaccinated were 49 percent less likely to develop long COVID after infection with COVID-19.

However, Montecalvo noted that some people may still suffer from moderate to severe illness.

There will always be exceptions for any variant, especially for people with underlying health conditions, Lillibridge said.

Tracking long-lasting COVID cases has been a challenge, as many health entities and countries have different practices and requirements for symptoms to be classified as such.

The UK, for example, says that for symptoms to be considered long COVID, patients must have had them for at least 3 months. While for the CDC, this delay is 4 weeks or more.

Also, because Omicron only appeared in November 2021, not enough time has passed for patients or doctors to notice signs of prolonged COVID.

All people infected with COVID-19, whether hospitalized or with only mild symptoms, can experience long COVID.

Studies showed that even mild cases of COVID-19 can trigger persistent symptoms.

In a recent interview, US infectious disease expert Dr. Anthony Fauci reiterated that long COVID was a possibility regardless of the variant.

“A long COVID can occur, regardless of the variant of the virus. There is no evidence that there is a difference between Delta or Beta or now Omicron,” he said.

Previous research has estimated, on average, up to 30 percent of patients develop long COVID.

Studies have also revealed that 1 of 7 children and young people may still show symptoms related to COVID-19 15 weeks after the initial infection.

Montecalvo pointed out that the long COVID could certainly be a result of Omicron infections, but at the moment its incidence rate was unknown.

Some experts believe the incidence of long COVIDs may be lower because Omicron does not appear to cause a high or persistent increase in inflammatory markers in the body during infection. Long COVID has often been more debilitating in severe cases with severe inflammation.

Andrew Catchpole, DPhil, virologist and scientific director of hVIVO, which conducts human challenge studies for infectious diseases, said he does not expect a higher incidence of long COVID cases in proportion to Omicron infections.

“Although Omicron is more infectious, infectiousness is not related to an increased likelihood of long COVID. It is more related to gravity. [As] on average, Omicron infections are less severe than seen with other variants or the original strain, we expect the proportion of long COVID cases to be lower with Omicron,” a- he told Healthline.

Catchpole said diagnosing long COVID depends on both the symptom and its duration.

“As for the symptoms associated with acute illness while the patient is contagious, we expect all of them to resolve within 10 to 14 days,” he told Healthline.

These symptoms can be a runny nose, sore throat, shortness of breath, fever, muscle aches, lethargy and even, on some occasions, diarrhea and nausea, he said.

“If one of these [symptoms] to persist any longer would be unusual. [A]anything that remains apparent 1 month after first symptoms appear warrants further investigation by a physician.
– Dr. Andrew Catchpole

Lillibridge said persistent shortness of breath, fatigue and trouble concentrating were the most bothersome symptoms that indicated the need for further investigation.

If you experience these or more symptoms after your infection and they persist beyond 2 to 3 weeks of recovery from your acute illness, follow up with your healthcare provider, he told Healthline. .

Catchpole also warned that two symptoms, in particular, might not be of concern when it comes to long COVID.

Catchpole said a loss of taste and/or smell can persist for weeks or months, with more than 3 months being relatively common.

“I would suggest speaking with their doctor anytime they are concerned about a symptom. You wouldn’t want to attribute a symptom to ‘long COVID’ that could be a manifestation of another problem,” Montecalvo said.

There have also been concerns about reinfections reigniting long COVID symptoms in people who had previously been infected with COVID-19.

Such a case is a Spanish healthcare worker who contracted the original strain in February 2020, the Delta strain in July 2021 and Omicron in November 2021.

The reinfections caused him chronic pain, fatigue and memory loss, among other symptoms.

It’s too early to tell if Omicron will lead to longer COVID cases and experts are divided.

One camp argues that the perceived reduction in disease severity and higher immunization will help protect against long COVID.

Meanwhile, others believe that Omicron’s high transmissibility will multiply the number of long cases of COVID, making the disease a chronic public health problem.

Although getting vaccinated greatly reduces the risk of developing long COVID, reinfection can cause a flare-up of symptoms.

If you have persistent symptoms such as brain fog, muscle aches, fatigue or the like after infection with COVID-19, it may be best to contact your healthcare professional and seek advice from a post-COVID care center in the United States.

Patient advocacy groups for people with long-term COVID, like Survivor Corps, are also good sources of information and emotional support.