Centre writes to states over new Covid variant: all you should know about JN.1

These steps come after at least one case of the new variant JN.1 was detected during routine surveillance in Kerala, the health ministry said. This variant was also detected in the sample of a traveller from Singapore to Tamil Nadu’s Tiruchirapalli, according to the ministry.

Another 15 cases of the JN.1 variant were detected in samples from Goa, according to officials familiar with the matter.

What do we know about JN.1?

The sub-variant JN.1 is a descendant of the BA.2.86 variant, commonly referred to as Pirola, and is not exactly new. The first cases of this variant were detected in the United States in September and the first case globally was detected as early as January this year.

While JN.1 contains only one additional mutation on the spike protein as compared with Pirola, it has been on the watch-list of researchers because Pirola contains more than 30 mutations on the spike protein. Mutations on the spike protein of Sars-CoV-2 matter because they are the ones that attach to receptors on a human cell and allow the virus to enter it.

Can it lead to a surge, or more severe symptoms?

There is no evidence to suggest that JN.1 can cause worse symptoms or spread faster than the variants already in circulation. Initially, there were concerns that the high number of mutations could mean that Pirola would evade immune response more easily and spread rapidly. That, however, hasn’t happened.

In fact, an assessment by the WHO Technical Advisory Group on COVID-19 Vaccine Composition showed that Pirola and JN.1 were both effectively neutralised by serum from humans who had had the infection and vaccination.

While Pirola and JN.1 are considered to be Variants of Interest (variants that are less effectively neutralised in labs by antibodies from infection or vaccination and have a potential to spread), they have not been designated as Variants of Concern (variants that result in increased transmission, severe disease leading to hospitalisation, and reduce effectiveness of vaccines).

What has led to the current concerns?

There is definitely an increase in the number of cases being caused by Pirola and its close relative JN.1 globally. Cases have been detected in the USA, some European countries, Singapore, and China.

A statement from WHO said that Pirola and its descendants accounted for 17% of the Sars-CoV-2 sequences uploaded to the global database Global Initiative on Sharing All Influenza Data (GISAID). By the beginning of December, more than half of these sequences were that of JN.1. In the United States, JN.1 accounted for 15% to 29% of the circulating Covid-19 variants.

Singapore has recorded an estimated 56,043 cases during the week of December 4 to 10. It also saw an increase in hospitalisation, mostly among those above the age of 60. “Cases infected by JN.1, a sublineage of BA.2.86, currently account for the vast majority of the COVID-19 cases in Singapore. Based on the available international and local data, there is currently no clear indication that BA.2.86 or JN.1 are more transmissible or cause more severe disease than other circulating variants,” said Singapore’s ministry of health.

Do you need additional shots?

While data from Singapore shows that those who had received their last Covid-19 vaccine dose more than a year ago were 1.6 times more likely to need hospitalisation, experts said that a wide coverage of vaccination and subsequent non-symptomatic infections are likely to have resulted in a significant level of protection in India.

“Most Indians have been exposed to Covid-19 at least two, or perhaps even three times, and have also received at least two doses of the vaccine. With a good level of immunity in the population — which can prevent severe disease — updated vaccines are not really needed in India,” said Dr Anurag Agarwal, dean of biosciences and health research at the Trivedi School of Biosciences of Ashoka University and member the WHO’s Technical Advisory Group on Sars-CoV-2 Virus Evolution.

How can you protect yourself?

Experts say that while new variants of Sars-CoV-2 will keep emerging, protective measures against a respiratory virus remain the same. Doctors suggest masking up in crowded areas, especially enclosed ones, if the number of cases is increasing locally. Remaining in well-ventilated spaces reduces the spread of the infection. Also, washing hands frequently prevents the infection.