India is witnessing a renewed rise in Covid-19 cases, with active infections surpassing 1,000 as of late May 2025. Kerala leads with over 430 active cases, followed by Maharashtra, Delhi, and Gujarat, while smaller increases are seen in Karnataka, Tamil Nadu, and West Bengal. The surge is linked to the detection of two new subvariants, NB.1.8.1 and LF.7, which are currently classified as Variants Under Monitoring by the World Health Organization, not as Variants of Concern. These subvariants have been identified through genome sequencing, and their spread coincides with similar trends in Southeast Asia, notably Singapore.

Several factors are driving this uptick. Waning immunity from previous infections and vaccinations is a significant concern, especially among the elderly and immunocompromised. The emergence of new subvariants, such as NB.1.8.1—a descendant of the JN.1 lineage—demonstrates the virus’s ongoing evolution, though there is no evidence yet that these variants cause more severe illness. Seasonal changes, particularly the early arrival of the monsoon and increased humidity, may also be creating favorable conditions for the virus to spread, similar to other respiratory pathogens.

Another key factor is reduced surveillance. Routine testing and genomic sequencing have been scaled back since Covid-19 was declared endemic, delaying the detection of new variants and outbreaks. The relaxation of public health measures, including mask mandates and social distancing, is also contributing to increased transmission, especially among vulnerable groups. Public health authorities are responding by ramping up testing among those with symptoms and maintaining hospital preparedness, particularly in states with higher caseloads.

Despite the rise, most new cases are mild, and there is no indication of increased severity or a spike in hospitalizations. Experts advise caution but not panic, recommending that older adults, pregnant women, and those with underlying health conditions continue to take precautions such as wearing masks in crowded spaces and practicing good hygiene. The situation remains under close monitoring, with health officials emphasizing the importance of vigilance as the virus continues to circulate.