New Covid-19 Variant NB.1.8.1 is Highly Contagious, Warn Experts; What We Know So Far

The new, highly contagious Covid-19 variant NB.1.8.1 has been detected in the United States, according to the Centers for Disease Control and Prevention (CDC). CDC has also confirmed that NB.1.8.1 has triggered a sharp rise in hospitalisations across China.

The strain was first detected was first reported in the US between late March and early April among international travellers arriving at US airports. A few reports suggest that additional cases have been reported in Ohio, Rhode Island, and Hawaii.

Reports suggest that Hong Kong has reported 81 severe cases and 30 deaths linked to the variant in just four weeks, particularly individuals aged 65 and above.

Health experts in the US have emphasised that while NB.1.8.1 does not appear to cause more severe illness, it is spreading faster than earlier variants. "What they're seeing in China, Hong Kong, and elsewhere is a sharp uptick in hospitalisations," Dr. Amy Edwards of Case Western Reserve University told CBS.

About NB.1.8.1

NB.1.8.1 is a descendant of the Omicron family. Like other Omicron sub-variants, NB.1.8.1 appears to be highly transmissible. While the World Health Organisation has not classified it as a variant of concern, experts have warned that it can spread rapidly.

The new variant does not have any unique characteristics. Symptoms are generally mild to moderate. However, elderly and immune-compromised people remain at higher risk for severe disease.

Symptoms of NB.1.8.1

Infected individuals have reported symptoms that are quite similar to those of other omicron variants, including fever, cough, sore throat, headache, loss of appetite, body aches, fatigue, and runny nose.

What should you do?

"There is no need to panic at the moment. Most cases have reported mild symptoms of upper respiratory tract infections like cough, cold, slight breathlessness, fever, body ache and malaise. Severe outcomes are rare due to gained immunity and milder variants," said Dr Mohit Saran, Consultant - Internal Medicine And Diabetologist at Manipal Hospital, Gurugram.

However, it is important to remain cautious. Wear a mask, practice frequent handwashing, avoid large gatherings and crowded places and seek medical help if you have symptoms.

Dr. Edwin Tsui, head of the Centre for Health Protection, Hong Kong said that the variant "should not be taken lightly" and may be more capable of evading current vaccine protection.

Till now, less than 20 NB.1.8.1 cases have been reported in the US which is relatively low. However, experts are raising concerns about the variant's rapid spread in China and parts of Asia, where it has already become the dominant strain.

In India, NB.1.8.1 was first identified in Tamil Nadu in April 2025.

Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.