The COVID-19 NB. 1.8.1 or Nimbus variant has not yet been detected in the Philippines, the Department of Health said on Sunday, June 22. In a Teleradyo interview, DOH Assistant Secretary Albert Domingo said the virus — also called the “razor blade variant” — is categorized as low risk by the World Health Organization (WHO) even as cases are detected abroad.
In the U.S., the Nimbus variant accounts for 37 of reported COVID-19 cases as of early June 2025, according to the Centers for Disease Control and Prevention (CDC). The variant is also “under monitoring,” but is not yet categorized by the WHO as a “variant of interest” or a “variant of concern.”
Dr. Peter Chin-Hong of the University of California San Francisco tells ABC News that the virus appears to be more transmissible because of its mutated spike protein, which helps it attach to and infect cells.
However, Domingo says cases remain mild. “Ang outlook ng WHO dito sa NB.1.8.1 ay low risk pa rin,” Domingo said. “Ibig sabihin ang bilang ng mga tao, bagama’t dumadami ang kanilang sintomas ay mild pa rin. Ang pagkaospital ay hindi tumataas.”
‘Razor Blade Throat’ and Other Symptoms
The Nimbus variant’s symptoms are very much like those of previous strains, including coughing, fever, chills, shortness of breath, nausea, and sore throat. Those infected with Nimbus have also reported razor-sharp pain in the throat, but it may not be distinct to the variant, or other common viruses like the common cold influenza, and bacterial infections like strep throat.
“I think it’s certainly amongst the spectrum of symptoms that you can get, and we know that sore throat is reported by about 70 percent of patients now with COVID, so it’s not unusual,” Chin-Hong said.
Domingo assured that vaccines administered during the government’s mass vaccination program in 2021 and 2022 remain effective against the new strain. “Kung nakuha natin iyon, epektibo pa rin iyon laban dito, kasi itong NB.1.8.1 ay sabihin na nating kapamilya ni Omicron,” he said.
As of May, the Philippines has only recorded 1,774 COVID-19 cases this year, a significant improvement from the 14,074 cases reported in 2024.
