New COVID-19 Variant NB.1.8.1 (Nimbus) Sparks Global Concern Over 'Razor Blade Throat' Symptom
| Category | Details |
|---|---|
| Variant Name | NB.1.8.1 (informally called Nimbus) |
| Lineage | Descendant of Omicron |
| First Identified | January 2025 |
| Key Symptom | "Razor blade throat" (severe sore throat) |
| WHO Status | Listed as a variant under monitoring (VUM) |
| Global Spread | Detected in 22 countries, including US, UK, China, Singapore, Thailand; accounts for 10.7% of sequenced cases (April 21-27, 2025) |
| Severity | Low risk per WHO; mild to moderate illness; no major hospitalization surge |
| Vaccine Efficacy | Current vaccines remain effective |
| India's Status | No confirmed Nimbus cases yet; daily COVID cases stable (100-200); rise in H3N2 and adenovirus cases |
| Other Variant | XFG (Stratus) - another Omicron subvariant, not under WHO monitoring |