India is witnessing a concerning spike in Covid cases, particularly in states like Maharashtra, Karnataka, and Tamil Nadu, amid rising fears around the newly identified COVID-19 Variant NB.1.8.1. Health departments across the country are on high alert as daily infection numbers slowly climb and testing and surveillance have ramped up in recent weeks.
Covid-19 Resurgence: States On High Alert Again
After months of steady decline, Covid-19 cases are beginning to resurface in multiple Indian states. According to recent government health reports, Maharashtra has reported over 650 new Covid cases in the last two weeks, with Karnataka and Tamil Nadu following closely with daily figures fluctuating between 200–500 cases per day.
The Centers for Disease Control and Prevention (CDC) has confirmed the presence of NB.1.8.1, a highly contagious Covid-19 variant that has driven a surge in hospitalizations across China. The strain was first detected in international travellers arriving at US airports between… pic.twitter.com/p1enHv4Ilz
— IndiaToday (@IndiaToday) May 28, 2025
Source: India Today
Experts suggest that the NB.1.8.1 variant—a sublineage of the Omicron strain—could be partly responsible for this surge. Although it hasn’t yet been classified as a “variant of concern” by the WHO, its increasing footprint across southern India has prompted state health agencies to issue fresh guidelines for testing, isolation, and masking.
What is the NB.1.8.1 Covid-19 Variant?
The COVID-19 Variant NB.1.8.1 is a recently identified offshoot of the Omicron lineage. Early research suggests that this strain might possess mutations that help it evade certain immune responses. However, current evidence doesn’t indicate it causes more severe disease than previous variants.
Key facts about NB.1.8.1:
- Related to Omicron, known for high transmissibility
- No confirmed data on vaccine resistance yet
- Found in a rising number of RT-PCR samples in southern India
- Mild symptoms in most reported cases
Read Also: COVID-19 Surge in India, Singapore, and Hong Kong: Health Ministries on High Alert
Source: WION
Maharashtra’s Growing Numbers: A State of Caution
Health authorities in Maharashtra, which was previously the epicenter during earlier waves, have reported a consistent rise in Covid cases. Mumbai, Pune, and Thane have seen localised outbreaks, mostly in housing societies, schools, and IT offices.
In response:
- Mumbai has resumed random testing at crowded areas like malls and railway stations
- Hospitals have been instructed to refresh Covid wards and staff availability
- The Brihanmumbai Municipal Corporation (BMC) has advised wearing masks in closed public places
- According to BMC data, the positivity rate has gone up to 2.3%, a noticeable increase from last month’s 0.6%.
Karnataka’s Preparedness: Bengaluru Leads Monitoring
Karnataka, particularly Bengaluru, is another hotspot where the Covid-19 curve is starting to turn upward again. Although hospitalizations remain low, the number of daily cases has nearly doubled compared to last month.
State health officials have:
- Reintroduced thermal screening at bus stands and airports
- Set up mobile testing camps near tech parks and educational institutions
- Asked citizens to report flu-like symptoms and get tested proactively
With Bengaluru being a tech hub, many IT companies have paused return-to-office plans and are once again opting for hybrid work arrangements to minimize transmission.
Tamil Nadu Reports Rising Infections Amid Festival Season
Tamil Nadu has seen a sharp increase in Covid cases, especially in Chennai and Coimbatore. The festival season, which brought large gatherings and travel, is suspected to have contributed to this uptick.
Chennai alone accounted for more than 60% of the new infections last week, with the NB.1.8.1 variant detected in nearly 20% of samples sequenced.
Precautionary measures in Tamil Nadu:
- Awareness campaigns launched in rural and urban areas
- Distribution of free masks and hand sanitizers
- Surveillance intensified at public health centers
Despite the rise in cases, the state government has not reimposed restrictions but continues to monitor the situation closely.
India’s Covid-19 Situation at a Glance
| State | Daily Average Cases | Dominant Variant | Positivity Rate |
| Maharashtra | 400–650 | NB.1.8.1 | 2.3% |
| Karnataka | 250–450 | NB.1.8.1 | 1.9% |
| Tamil Nadu | 300–500 | NB.1.8.1 | 2.1% |
Symptoms Reported With NB.1.8.1 Variant
Though mostly causing mild illness, the symptoms of the NB.1.8.1 variant should not be overlooked.
Common symptoms include:
- Low-grade fever
- Sore throat
- Runny nose
- Body ache
- Fatigue
- Occasional shortness of breath in older individuals
Doctors recommend seeking medical help if symptoms persist for more than three days or worsen suddenly.
What the Experts Are Saying
Dr. Neeraj Gupta, a virologist at the National Institute of Virology, Pune, stated:
“NB.1.8.1 appears to be behaving similarly to previous Omicron subvariants. Most cases are mild, but the virus’s evolution remains unpredictable.”
Meanwhile, public health expert Dr. Radhika Nair added:
“Our healthcare system must not take the situation lightly. Continuous surveillance and genome sequencing will help us stay ahead of any surprise turns.”
Government Guidelines for the Public
The Ministry of Health has issued fresh advisories to prevent further spread of Covid-19:
Get tested if symptoms emerge
- Isolate for at least 5 days if tested positive
- Wear masks in crowded or enclosed spaces
- Wash hands frequently
- Avoid unnecessary travel to outbreak-prone areas
State-specific guidelines may vary slightly, but the core principles remain consistent.
Vaccination: Still the First Line of Defense
Even as new variants like NB.1.8.1 emerge, vaccines continue to offer strong protection against severe disease and hospitalization. Booster dose coverage, however, remains suboptimal.
Current vaccination status:
- Maharashtra: 91% first dose, 79% second dose, 43% booster
- Karnataka: 93% first dose, 81% second dose, 40% booster
- Tamil Nadu: 89% first dose, 76% second dose, 38% booster
Doctors are urging eligible individuals, especially seniors and those with comorbidities, to take their booster shots promptly.
The Way Forward: Stay Alert, Not Alarmed
While the current rise in Covid cases does raise red flags, it’s not yet a sign of another full-blown wave. The health infrastructure in most states has shown resilience, and previous experience with managing outbreaks is proving helpful.
Here’s what you can do:
- Monitor your health
- Stay informed through credible sources
- Avoid forwarding unverified information
- Continue basic hygiene and masking protocols
Conclusion
The resurgence of Covid-19 in Maharashtra, Karnataka, and Tamil Nadu, possibly linked to the COVID-19 Variant NB.1.8.1, underscores the need for collective vigilance. While no state is heading toward lockdown, precautions and readiness at both individual and community levels are key to keeping the situation under control.
India has come a long way since the first outbreak of Covid-19, and with the right public response, this current surge can be managed effectively. Stay safe, stay informed.