India is witnessing a cautious uptick in COVID-19 cases driven by two new sub-variants—NB.1.8.1 and LF.7—both descendants of the dominant JN.1 lineage of Omicron. While these variants are more transmissible and show some ability to evade immune protection, they do not currently appear to cause severe illness in most individuals.
Here’s what’s important to know:
Where have these variants been detected?
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NB.1.8.1: Detected in Tamil Nadu (1 case in April).
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LF.7: Found in Gujarat (4 cases in May).
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Noida, Uttar Pradesh: A 55-year-old woman tested positive, marking the district’s first known case in the current wave.
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AIIMS Rishikesh (Uttarakhand): Reported 3 cases; one patient discharged, others under observation.
What are NB.1.8.1 and LF.7?
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Both are sub-lineages of JN.1, the most dominant variant in India right now, accounting for over 53% of sequenced cases.
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Classified by WHO as "Variants Under Monitoring"—they have concerning mutations, but are not yet proven to be dangerous enough for higher-level alerts.
Notable Mutations:
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NB.1.8.1: Has spike protein changes like A435S, V445H, and T478I, which may improve its ability to infect and dodge immunity.
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JN.1: Carries L455S, estimated to make it 1.5 times more infectious than prior Omicron sub-variants.
How serious is the situation?
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Severity is low: Most infections are mild, with low hospitalisation rates.
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According to experts, comorbidities and age remain key risk factors.
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Current symptoms resemble typical upper respiratory infections—fever, sore throat, mild cough, and fatigue.
Why are cases rising now?
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Waning immunity (especially among those who haven’t had boosters).
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Booster coverage is uneven, particularly in vulnerable groups.
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Improved genomic surveillance is catching more cases.
Latest Case Numbers (as of May 19):
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Active cases: 257 nationwide.
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New cases last week: Over 750, with:
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Kerala: ~400 cases
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Delhi: >100 cases
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Hotspots: Mumbai, Pune, Thane, Chennai, and Ernakulam
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Government Response:
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Delhi has issued advisories for hospitals to ensure readiness (beds, oxygen, drugs).
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Surveillance and contact tracing have been stepped up.
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No talk yet of lockdowns or large-scale restrictions.
What about vaccines?
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No variant-specific vaccines are available yet in India.
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However, existing boosters offer solid protection:
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~50% protection from symptomatic infection.
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~80% protection from severe disease.
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Expert Advice:
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Dr. Meenu Singh (AIIMS Rishikesh): Current variant not very harmful, but vulnerable people should be cautious.
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Dr. Arup Halder (CMRI, Kolkata): Urges booster vaccination, continued mask use, and hygiene.
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Dr. Suranjit Chatterjee (Apollo, Delhi): No need to panic; situation under control.
Bottom Line:
These new sub-variants are not causing a major health crisis yet, but vigilance is essential. High-risk individuals should get boosted, wear masks in crowded places, and stay alert to symptoms. Public health agencies are monitoring closely to prevent any major resurgence.
