‘Razor Blade Throat’ Is Common Sign of New Covid Variant, Doctors Say

Sore throat has been known to be one of the first signs of a COVID-19 infection — and now a specific version of the symptom, referred to as “razor blade throat,” is being associated with the newest COVID strain, called NB.1.8.1.

However, a severe sore throat can be a sign of many different illnesses, so it’s important to take precautions if you experience this symptom this summer, experts say.

“A ‘razor blade throat’ is a very descriptive term describing severe sore throat pain — as if their throat is covered with razor blades — (like) with various viral infections,” Dr. Aaron Glatt, chair of the department of medicine and chief of infectious diseases at Mount Sinai South Nassau in New York, tells TODAY.com.

“While not specific to COVID-19, this expression has been used to describe sore throat symptoms in some patients with the most recent COVID-19 variant.”

Although COVID levels in the U.S. are currently low overall, according to wastewater data from the U.S. Centers for Disease Control and Prevention, there are many people who’ve reported experiencing razor blade throat in recent weeks.

And the symptom may become more common this summer, if cases continue to rise. In previous years, COVID-19 has surged in the summer, which is likely to be the case in 2025 as well, but it’s unclear how severe the wave will be or how long it will last.

Here’s what to know about “razor blade throat” and the new COVID variant.

New COVID Variant NB.1.8.1 Causes ‘Unusual’ Symptoms

T. Ryan Gregory, an evolutionary biologist who’s coined several catchy names for COVID variants, nicknamed the variant “Nimbus” on X in late May.

“It is a variant of the omicron strain of COVID,” Dr. Paulette Pinargote Cornejo, infectious disease specialist at Ochsner LSU Health, tells TODAY.com.

“With Nimbus, we are seeing usual symptoms, such as runny nose, fever, nausea and vomiting, along with what some are calling ‘razor blade throat,’ an incredibly painful sore throat,” Cornejo adds.

The variant, first discovered in China this past January, has genetic changes that could make it easier to spread and evade the immune system.

“As with all new variants, there is always a concern that prior immunity may not be as protective,” Glatt says.

But it does not appear more virulent — meaning it likely will not cause more severe disease compared to previous ones that came before it.

It still poses a higher risk for vulnerable groups, such as the elderly, those with weakened immune systems and individuals with underlying health conditions, Cornejo says.

“The best way to prevent any virus infection is to continue practicing good hand hygiene by frequent hand-washing or the use of hand sanitizer,” she adds.

Where Is the New COVID Variant Spreading?

The World Health Organization labels NB.1.8.1 as a “variant under monitoring” — meaning it is spreading fast enough to raise public concern, but it is still not a major threat.

It made up 10.7% among all COVID-19 samples world-wide in May compared to 2.5% a month earlier, according to a recent WHO report.

The U.S. Centers for Disease Control and Prevention said Nimbus activity increased from 15% to 37% of new COVID cases in late May, putting it essentially on par with LP.8., the dominant variant over the past few months (now circulating at 38%).

“The new predominant strain of COVID-19 we are seeing now is the NB.1.8.1,” Cornejo says.

COVID activity level in the U.S. is still “very low,” according to the latest CDC wastewater data from the week ending June 7. But it is expected to rise in coming weeks, experts say.

What Is ‘Razor Blade’ Throat?

Razor blade throat occurs when there is severe pain in the throat due to a virus directly infecting the cells of the oropharynx, or the back of the mouth. The lining, or mucosa, gets inflamed.

But the symptom is not unique to the new COVID variant.

Many different illnesses can cause extreme throat pain — most commonly viruses, like the common cold and influenza, as well as bacterial infections, like strep throat. Allergies, irritants in the air, smoking and acid reflux can also cause sore throat, medically referred to as “pharyngitis.”

How Do You Treat Razor Blade Throat?

The treatment for sore throats depends on the underlying cause, but when it’s a virus, like COVID-19, it usually targets symptoms.

Some common home remedies include:

• Gargling saltwater (mix half-teaspoon salt in 1 cup of lukewarm water)

• Lozenges for anyone older than 4
• Honey for anyone 1 year or older
• Sucking on ice chips or popsicles
• Clean humidifier or cool mist vaporizer
• Warm drinks and plenty of fluids

• Anti-inflammatories like ibuprofen (talk to health provider before giving to children)

What If ‘Razor Blade Throat’ Doesn’t Improve?

Most sore throats generally get better within one week. If it doesn’t improve after a week, see a health care provider to rule out other possible causes, such as:

• Infectious mononucleosis (mono)
• Sexually transmitted infections, like HIV, syphilis, gonorrhea or chlamydia
• Serious bacterial infections, like tularemia
• Vaccine-preventable diseases, like diphtheria
• Non-infectious causes, like medications and autoimmune diseases, like Kawasaki disease and Behcet syndrome

To reduce your risk of developing razor blade throat from a COVID-19 infection, wash your hands regularly, consider masking in crowded, indoor spaces, and stay up to date on your COVID vaccinations, experts say. And don’t forget to take a COVID test if you develop symptoms so you can avoid spreading it to others.