Does the Omicron COVID Variant Cause Different Symptoms?

The newly-detected Omicron variant is the predominant strain of COVID-19 in the United States. The the Centers for Disease Control and Prevention (CDC) has marked it as a Variant of Concern (VOC), along with the Delta Variant.

Because Omicron contains multiple mutations, will it cause different symptoms than the Delta variant—the only other VOC in the U.S.? It may be too soon to tell.

How Does Omicron Compare to Other Variants?

Because the Omicron variant was discovered fairly recently, there are several questions that have yet to be answered, Mahdee Sobhanie, MD, infectious diseases physician at The Ohio State University Wexner Medical Center, told Verywell. This includes the following:

• Its transmissibility
• The severity of the disease it causes
• Whether current vaccines and COVID-19 therapies will hold up against it
• Whether it will outcompete the Delta variant

“I anticipate over the next couple of weeks there will be more data emerging worldwide that should provide answers to these questions,” Sobhanie added. 

Does Omicron Cause Different Symptoms?

When Delta became the predominant variant, cold-like upper respiratory symptoms became more common, while the loss of taste and smell became less common than before.

“There are also a lot of other factors which have to be taken into consideration when we look at symptoms caused by different COVID variants, such as vaccination status, age, and whether patients have other medical problems that put them at higher risk of developing severe disease,” Sobhanie said.

Like Delta, the Omicron variant can also cause a change in the prevalence or severity of symptoms. However, more data is needed to know for certain.

“Preliminary reports suggest patients infected with the Omicron variant have similar symptoms to other variants of SARS-CoV-2,” Scott Roberts, MD, Yale Medicine infectious diseases specialist and assistant professor of medicine at Yale School of Medicine, told Verywell. “There are anecdotal reports of cases being milder and patients having no loss of taste or smell, however, these are anecdotal and should be interpreted with caution until more data is available.”

The New York Times reported that researchers at a major hospital complex in the capital of South Africa found that their COVID-19 patients were much less sick than those they've treated in the past. But, as Roberts stated, these reports are still anecdotal.

According to the World Health Organization (WHO), early evidence suggests that there may be a higher risk of reinfection with the Omicron variant. It may also spread more easily than other variants, including Delta. 

“We do not yet know for certain whether the Omicron variant is more transmissible than the Delta variant until more data is available,” Roberts said, “However the Omicron cases currently outpacing the Delta cases in parts of South Africa is concerning and indicates this variant is likely more transmissible than other previously recognized variants.”

Every time a virus mutates, there are genetic changes that occur, which explains why different COVID-19 variants have varying symptoms and transmissibility.

“Variants are distinguished by mutations in the genetic code of the virus,” Roberts said. “Some of these mutations can impact the behavior of the virus and impact symptomatology and transmissibility. For example, mutations in the spike protein can impact how well the virus binds to and enters human cells.”

Get Your Vaccine and Booster

Anecdotal reports about milder cases of COVID-19 caused by Omicron don't mean you should take the possibility of infection lightly.

“Any person who has had COVID-19 is at risk for post-COVID conditions,” Roberts said. “While post-COVID-19 conditions are more common in severe disease, even people with mild COVID-19 can have post-COVID-19 conditions, and the best prevention is to not get infected in the first place.”

According to CDC, even individuals who had asymptomatic infections are at risk for post-COVID conditions. More research is needed to fully understand the cause, prevalence, and treatment of post-acute COVID syndrome.

Preventing COVID-19 is the best way to protect yourself from any long-term effects of the disease. At the moment, the emergence of the Omicron variant does not change current COVID-19 safety precautions or prevention strategies.

“Right now there are 90,000 to 100,000 cases of COVID diagnosed daily in the United States, and the predominant strain is Delta,” Sobhanie said. “We know that the current vaccines do well against the Delta variant, hence if you are not fully vaccinated—you should get vaccinated. And if you are eligible to be boosted, get boosted. Masks are still incredibly important and effective, so if you are in an area with a high transmission rate, you should wear a mask.”

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.