After a pleasant lull of over a year during which Covid-19 was not making headlines, the virus is back in the news. On December 19, 2023, the World Health Organisation classified the JN.1 variant, a descendent of the BA.2.86 Omicron lineage, as a ‘variant of interest’. This was done because this strain of SARS-Co-V-2 is spreading rapidly, leading to an uptick in cases globally, including in India. However, the WHO has said that with the available evidence, the additional public health risk posed by JN.1 is currently evaluated as “low” at the global level
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Many parts of India have seen a rise in Covid-19 cases as well, with current active cases at over 4,000. Fatalities too, have risen marginally. While the Union Health Ministry has asked the State government to stay alert and prepare for a surge, government authorities and doctors have said that while residents must remain vigilant and take precautions, there is no need to panic.
What causes the coronavirus to mutate, and how is its spike protein involved? The spike (S) protein is one of the key biological characteristics of Sars-CoV-2. This protein allows the virus to penetrate into the cells of its host (human beings) and cause the infection. This means that without the S protein, the virus would not be able to infect human beings, and so, this is a protein that is of interest to scientists making vaccines and anti-viral drugs.
In its initial risk evaluation, the WHO said that previously, JN.1 was tracked as part of BA.2.86, the parent lineage that is classified as a variant of interest. The earliest sample of JN.1 was collected on August 25, 2023. In comparison with the parent lineage BA.2.86, JN.1 has the additional L455S mutation in the spike protein.
A paper published in The Lancet Infectious Diseases said that the L455S mutation may slightly reduce JN.1’s ability to bind to human cells, but may have increased this sub-variant’s immune evasion properties.
Also Read: COVID-19: Variants of Concern and Variants of Interest
The challenge has always been making effective drugs and vaccines when the virus is constantly mutating, points out Deepak Sehgal, professor, department of life sciences, Shiv Nadar Institute of Eminence, Delhi. Prof Sehgal, along with his student Aditya Trivedi and others, recently published a paper in the FEBS Journal on their research about an inhibitor that can bind to the viral proteins of the coronavirus in order to prevent its replication. This, he said, could eventually help the development of drugs to treat Covid-19.
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Will the current Covid-19 vaccines work? The Centers for Disease Control and Prevention, in an update issued earlier this month, said there was no indication of increased severity from JN.1 at this time. Existing vaccines, tests, and treatments still work well against JN.1, the bulletin stated.
The Pune-based Serum Institute of India (SII), has said it will be “aiming to obtain licensure for XBB1 COVID variant vaccine which is very similar to the JN.1 variant for use in India,” as reported by The Hindu previously.
Do we need booster shots of vaccines? Subramanian Swaminathan, vice president, Clinical Infectious Diseases Society, India, says that given that the JN.1 strain seems to have significant immune evasion, another dose of the same vaccine may not provide added protection. “A majority of people in India have hybrid immunity. Since we cannot give people a new vaccine immediately, and since this surge in cases is likely to conclude by the end of January, the benefits of a booster of the same, previous shot, are low. Those who are immuno-compromised however, could consider a booster shot,” he says, adding that there are now multiple treatment options for patients, provided the infection is picked up early.
A booster shot could help protect vulnerable populations, Prof Sehgal adds. Masks, hand-washing and avoiding crowded places must continue, especially for senior citizens and those with co-morbidities, he emphasises.
“Covid is here to stay. We need to learn how to take precautions and live with it,” says Prof Sehgal.
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