Why Is the ‘Nimbus’ COVID Variant Spreading So Quickly?
United States
Thu, 14 August 2025 Thursday, 14 August 2025
Health
3 - 4 minutesHealth officials in the United States are warning about a new COVID-19 variant known as NB.1.8.1, or “Nimbus.” It is now responsible for more than forty percent of reported cases and has been detected in forty-five states. The nickname comes from the way patients often describe a thick, cloud-like pain in the throat. While it appears more transmissible than earlier strains, scientists say there is no clear evidence that it causes more severe illness or higher rates of hospitalisation.
The Centers for Disease Control and Prevention (CDC) reports that most cases are mild to moderate, with symptoms including fever, cough, and severe sore throat. Another variant, called XFG or “Stratus,” has also emerged but remains far less common and is not considered a major public health threat. Experts stress that testing and genomic sequencing are critical for tracking how these variants evolve and spread within communities.
Public health advice remains consistent. Vaccination and booster shots continue to provide strong protection against serious illness. Wearing a mask in crowded indoor spaces, improving ventilation, and staying home when feeling unwell can all help reduce transmission. The CDC encourages people to remain cautious, particularly in areas where case numbers are rising quickly, to avoid another period of uncontrolled community spread.