Symptoms, health risks: All you need to know about Nimbus, most common Covid variant in US

Detected in several US states back in June, the Nimbus variant of Covid-19 is now reportedly the most common in the country.

Officially known as NB.1.8.1 and nicknamed 'Nimbus', a new Covid-19 variant is now the dominant one in the United States. Detected in several US states back in June, the strain is now the most common in the country, according to the US Centers for Disease Control and Prevention.

The CDS is monitoring the spread of his virus through an airport screening program (REUTERS/Representational)

The CDS is monitoring the spread of his virus through an airport screening program, wherein nasal and wastewater samples are being collected.

From symptoms and spread to the health risks, here's all you need to know about the new variant:

• The 'Nimbus' variant was first detected in March by the CDC’s airport testing program, and is a subvariant of Omicron variant of SARS-CoV-2. It emerged in China earlier in 2025, and later spread to parts of Asia and Europe, a Bloomberg report said.
• Some people who have been diagnosed with the 'Nimbus' variant reported intense scratchiness like “razor blades in the throat".
• Other symptoms linked to the variant are common -- congestion, fatigue, mild cough, fever, loss of taste and smell, runny nose, loss of appetite and muscle aches.
• The variant makes up between 13-68 per cent of circulating Covid strains, according to a spokesperson for the Department of Health and Human Services. A two-week period ending June 21 showed 43 per cent of Covid cases being that of the Nimbus variant.
• However, Rajendram Rajnarayanan, a researcher at New York Institute of Technology, believes that the estimates of the Nimbus variant cases are unreliable "due to limited surveillance".
• While the CDS says it is “aware of increasing detections” of Nimbus, the World Health Organisation had earlier said that the public health risk the variant poses is not higher than others.

Cases of Nimbus variant were earlier detected in US states like Washington, New York, California and Virginia, and in other countries, like Australia and the UK.