Does Omicron COVID Variant Cause Loss of Taste and Smell?

Experts say the only real way to tell if you have COVID is through testing, but how can you know if you have omicron or delta if you test positive?

It's a question many are asking as omicron cases surge into the new year following holiday gatherings. Rapid and PCR testing only tell you if you have COVID, but they won't tell you which variant you have, unless your sample gets sent to a lab for further analysis.

Doctors have said symptoms can vary based on vaccination status, but with omicron causing a rise in breakthrough infections, some are noticing one symptom in particular may be changing.

Dr. Katherine Poehling, an infectious disease specialist and member of the Advisory Committee on Immunization Practices, told NBC News last month that a cough, congestion, runny nose and fatigue appear to be prominent symptoms with the omicron variant. But unlike delta, many patients are not losing their taste or smell.

The evidence so far, according to Poehling, is anecdotal and not based on scientific research. She noted also that these symptoms may only reflect certain populations.

Her comments echo those seen as the omicron surge first took hold in South Africa.

There, health officials advised people who suspected they contracted COVID-19 to watch out for common symptoms like a cough, fatigue or tiredness, congestion and runny nose.

But they noted the loss of taste and smell seems to be uncommon compared to other variants.

In a recent Nebraska omicron outbreak, five people were reinfected with COVID-19, according to a report from the CDC. Four of the individuals experienced loss of taste or smell during their first time with the virus, but none reported the symptoms during the second infection, the report stated.

Researchers studying an omicron-fueled outbreak at a Christmas party in Norway found that of the dozens of people who experienced symptoms, 12% reported reduced smell. Twenty-three percent reported reduced taste, the study showed.

Studies may only reflect certain segments of the population: young and otherwise healthy, as well as those who are fully vaccinated.

Chicago Department of Public Health Commissioner Dr. Allison Arwady, however, has said the symptoms with omicron aren't changing, but the increase in vaccinations is changing how many are responding to the virus.

Arwady said that now, those who are fully vaccinated aren't necessarily getting "seriously ill and having fevers for days and difficult breathing," but are instead experiencing a more mild illness.

"They may only feel like they have a cold," she said. "That's good because they're not getting seriously sick, they're not threatening the healthcare system, but it's certainly of some concern because they do have the potential to transmit to others."

The unvaccinated, however, are experiencing similar symptoms to early on in the pandemic, Arwady said.

Still, CDC data showed the most common symptoms so far are cough, fatigue, congestion and a runny nose.

Overall, the symptoms for COVID reported by the CDC include:

• Fever or chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue
• Muscle or body aches
• Headache
• New loss of taste or smell
• Sore throat
• Congestion or runny nose
• Nausea or vomiting
• Diarrhea