Hospitals across the United States are recording a disturbing surge in cases of what doctors are calling “Razor Throat COVID.”
The nickname comes not from science but straight from patients themselves, who describe the pain as if they were swallowing glass or jagged metal.
The culprit behind this vicious new wave is NB.1.8.1, also labeled as the Nimbus variant. Once a footnote in viral sequencing reports, it now accounts for more than one-third of all new infections across the country.
The spread has been swift. Just a month ago, NB.1.8.1 made up 5 percent of new COVID cases in the U.S. As of June 7, that number has spiked past 37 percent. It is no longer a fringe concern-it is now dominant.
Unlike previous variants, Nimbus is sparking fresh headlines not only due to its speed but because of the distinct way it tears through the throat of its victims.
Why Razor Throat COVID Feels So Brutal
The core symptom pushing this variant into public consciousness is its excruciating throat pain. It overshadows common flu-like signs and has even drawn comparison to strep throat in its most severe form.
Doctors report patients describing the sensation in language typically reserved for trauma: knives, razors, barbed wire.
Comparison With Previous Variants
Unlike Omicron’s runny nose and Delta’s dry cough, Nimbus presents with a concentrated burning and stabbing pain.
It often arrives without warning and can linger for up to ten days in severe cases. In many cases, it is the first and most intense sign of infection.
Where It’s Hitting and Who’s At Risk
The variant has now been confirmed in at least 14 U.S. states, including major hotspots like California, Texas, New York, Illinois, and Florida. International surveillance also shows confirmed outbreaks in parts of Europe and Asia, with China, South Korea, and the United Kingdom reporting sharp upticks in related strains.
Risk Profiles and Population Impact
Experts do not see increased hospitalization rates, but many clinics have reported spikes in urgent care visits due to the painful symptoms. While previously infected individuals and those who have completed vaccination cycles do seem to carry protection from severe outcomes, the sharp nature of the symptoms remains consistent across risk groups.
Those with compromised immune systems, chronic respiratory illnesses, or age over 65 remain vulnerable. Pregnant women and young children are seeing mixed outcomes, with many providers reporting difficulties securing up-to-date vaccines for these groups due to shifting federal guidance.
Full Symptom Profile of the NB.1.8.1 Variant
| Symptom | Severity Level | Notes |
|---|---|---|
| Razor-sharp throat pain | High | Most common, highly specific to this variant |
| Fever and chills | Mild to moderate | Appears later in progression |
| Dry or wet cough | Mild | Often accompanied by throat discomfort |
| Body aches and fatigue | Moderate | Similar to flu, can last 5 to 7 days |
| Nasal congestion | Moderate | Less common than in earlier Omicron waves |
| Nausea or diarrhea | Low | Seen mostly in children and older adults |
How Current Vaccines Are Holding Up
There is no consensus yet on how well existing vaccines block infection by NB.1.8.1, but federal officials are clear on one point: protection against severe outcomes remains strong. Laboratory studies suggest some degree of immune escape, meaning the variant may partially bypass immunity from older vaccines or previous infections. However, breakthrough infections do not appear to result in more hospitalizations than those caused by earlier Omicron subvariants.
Policy and Booster Updates
Federal agencies, including the CDC and FDA, are currently reviewing updated vaccine formulations for the fall. The next booster rollout may directly address the NB.1.8.1 lineage. Health authorities urge high-risk individuals to get vaccinated now if eligible, especially ahead of summer travel and large indoor gatherings.
Public Health Guidance: What You Should Do Right Now
Public health officials are not asking for lockdowns or sweeping mandates, but they are advising specific groups to take heightened precautions. Masking in crowded indoor spaces, especially with high-grade N95 respirators, remains effective. Regular handwashing and air filtration indoors continue to reduce transmission risk.
What To Do If You Experience Symptoms
People experiencing sudden, severe throat pain should isolate and get tested immediately. If positive, they are encouraged to consult a physician about antiviral treatment options such as Paxlovid or Molnupiravir. Those visiting elderly or immunocompromised family members should avoid large events for several days beforehand.
Community and Workplace Response
In workplaces and schools, sick leave and testing policies are once again under review, as summer break offers only a temporary reprieve. Long-term care facilities have also reintroduced some masking and distancing policies following new cluster outbreaks in California and Florida.
What Doctors Are Saying on the Front Lines
Physicians across major U.S. medical centers are describing the variant in unfiltered terms. Dr. Wesley Long of Houston Methodist said, “We are seeing a lot of people come in thinking they have strep, and it turns out to be NB.1.8.1. The pain is that intense.”
Dr. Peter Chin-Hong of UCSF added, “Sore throat is no longer just another symptom. For many, it is the defining feature. The term ‘razor throat’ may be dramatic, but it’s not far from what patients are actually feeling.”
What Comes Next
COVID does not appear to be vanishing anytime soon. Just as previous summer waves brought Alpha, Delta, and Omicron, this year may now belong to NB.1.8.1. The virus continues to mutate, and population immunity is shifting.
Whether the next vaccine update includes direct targeting of the Nimbus strain remains to be seen. But with rising infection rates and soaring clinic visits for throat pain, the trend is already underway.
Pain may not always indicate danger, but in the case of Razor Throat COVID, it is a sign worth watching closely.
References
- Johnson, C. (2025, June 18). What to know about the COVID variant that may cause ‘razor blade’ sore throats. Associated Press via AP News. https://apnews.com/article/4688df53917022cb61204e08b41d5952
- Nimbus COVID variant is spreading across the US. It’s likely in CT, health experts say. CT Insider. (2025, June 13). https://www.ctinsider.com/health/article/nimbus-covid-variant-2025-symptoms-vaccine-ct-20375921.php
- Nimbus COVID ‘razor blade throat’ reportedly like swallowing glass. What to know. Houston Chronicle. (2025, June 18). https://www.houstonchronicle.com/news/houston-texas/trending/article/covid-nimbus-razor-blade-throat-20382828.php
- ‘Nimbus’ new COVID variant: Tracking symptoms like ‘razor blade throat’. Fast Company. (2025, June). https://www.fastcompany.com/91351955/nimbus-new-covid-variant-tracker-symptoms-razor-blade-throat-nb-1-8-1-spreads-usa
- Shastri, D. (2025, June 18). What to know about ‘razor blade throat’ COVID. NBC Chicago via Associated Press. https://www.nbcchicago.com/news/national-international/nimbus-covid-variant-razor-blade-sore-throats/3771528/
- Lee, B. Y. (2025, June 14). ‘Razor Blade Throat’ symptoms as ‘Nimbus’ COVID-19 variant spreads. Forbes. https://www.forbes.com/sites/brucelee/2025/06/14/razor-blade-throat-symptoms-as-nimbus-covid-19-variant-spreads/
- COVID ‘razor blade throat’ rises as new subvariant spreads in California. Medical Xpress. (2025, June 17). https://medicalxpress.com/news/2025-06-covid-razor-blade-throat-subvariant.html
- WHO Monitors New Covid Variant Spreading in America and Europe. Wired. (2025, June). https://www.wired.com/story/who-monitors-new-covid-variant-nb181-spread-america-europe-nimbus/
