With the monsoon in full swing, multiple Indian cities are seeing renewed dengue activity, alongside stepped-up municipal action. In Mumbai, civic monsoon reports indicate higher overall vector-borne disease activity in 2025, with dengue infections rising versus last year through July; clinicians have flagged an OPD surge as humidity and waterlogging increase. Kolkata has recorded recent deaths and a cluster of fresh cases that have prompted the Kolkata Municipal Corporation (KMC) to intensify anti-dengue operations across several neighbourhoods. Lucknow has reported a steady climb in cases through mid-August as residents point to patchy fogging and waterlogging concerns. Nagpur has detected mosquito larvae in thousands of homes during door-to-door surveillance, triggering a citywide blitz on breeding sites.
This pattern is familiar: intermittent rains create small collections of clean water in and around homes, which are the perfect nursery for Aedes aegypti and Aedes albopictus, the day-biting mosquitoes that spread dengue. The good news: dengue is largely preventable with simple, consistent household measures. Here's what's been reported in these cities, unpack why cases typically rise now, and share evidence-based steps from Indian and global public-health authorities that you can implement today.
What Indian Cities Are Reporting
Mumbai
Brihanmumbai Municipal Corporation (BMC) data and hospital observations show rising vector-borne disease activity this monsoon, with dengue infections higher than 2024 through July and clinicians warning of increased OPD load as humidity and waterlogging persist. The BMC has issued advisories on stagnant water removal, nets/repellents, and fever vigilance.
Kolkata
Following two dengue deaths in mid-August, KMC has intensified vector-control drives in hotspots such as Ballygunge and Behala, and urged Puja committees to prevent water stagnation at pandals. Hospitals report a weekly uptick, with some patients showing gastro-intestinal symptoms alongside classic fever and body ache.
Lucknow
As of mid-August, Lucknow has seen a notable increase in dengue cases in the past 45 days, with residents citing waterlogging and clogged drains in several localities; the municipal corporation has initiated citywide cleanliness and insecticide-spray drives to curb breeding.
Nagpur
An intensive door-to-door survey in early August found mosquito larvae in nearly 8,000 of 1.46 lakh homes checked, prompting an NMC "dengue blitz" with fogging, larviciding and awareness campaigns. Reported case numbers since July remain in single digits but the larval index signals substantial transmission risk without sustained action.
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Why Dengue Cases Rise Now: The Science And The Season
Dengue risk typically increases during/after monsoon due to intermittent rainfall, humidity and waterlogging, which create numerous micro-containers (coolers, buckets, plant trays, tarpaulins, construction sites) for Aedes mosquitoes to lay eggs. These mosquitoes bite during the day and prefer clean, stagnant water-even tiny amounts are enough. Public-health guidance emphasises weekly elimination of standing water and screening of homes.
Clinically, dengue illness lasts 2-7 days of fever; warning signs (severe abdominal pain, persistent vomiting, mucosal bleed, lethargy, restlessness) often appear as the fever begins to subside, which is why medical advice discourages self-medication with NSAIDs and urges prompt evaluation for warning signs and adequate fluid management.
How To Stay Safe: Practical Steps For Families
Here are some science-backed methods of preventing dengue and keeping your family safe:
Eliminate mosquito breeding
Indian NCVBDC and WHO guidelines prioritise source reduction as the most effective first line of defence.
- Empty, scrub, dry: buckets, trays under flowerpots, AC drip pans, pet bowls, coolers, fridge trays, discarded tyres.
- Cover overhead tanks and drums; repair leaking taps.
- Check construction sites and terraces for pooled rainwater; escalate to RWAs if needed.
Personal protection, especially for day bites
CDC's dengue pocket guide and WHO recommendations endorse these measures for households.
- Use repellents on exposed skin (per label instructions); reapply as directed.
- Wear full-sleeved, light-coloured clothing; use window/door screens.
- Sleep under mosquito nets (helpful for sick family members to prevent household spread).
Photo Credit: Pexels
Community measures that work
NCVBDC's programme guidance stresses integrated vector management with community participation.
- Support fogging/larviciding drives but remember they are supplementary; they don't replace weekly source reduction at home.
- Report stagnant water and blocked drains to local civic bodies; many corporations run monsoon hotlines during this season.
When to seek care, and what to avoid
Clinical red flags or symptoms of dengue should not be taken lighty, so here's what you should note:
- Seek medical attention for high fever with headache, retro-orbital pain, myalgia/arthralgia, rash, or any warning signs (bleeding gums, black stools, persistent vomiting, severe abdominal pain, extreme weakness).
- Avoid ibuprofen or other NSAIDs until dengue is ruled out; use paracetamol for fever as advised by a clinician.
- Maintain oral fluids (ORS, coconut water, soups) unless restricted by your doctor.
Special precautions for vulnerable groups
- Pregnant women, young children, older adults, and those with comorbidities should seek early assessment if febrile during dengue season.
- Households with a confirmed dengue patient should adopt strict mosquito-avoidance to prevent further transmission at home.
This monsoon's dengue picture is evolving city by city: Mumbai hospitals and BMC reports indicate higher activity; Kolkata has intensified civic action after recent deaths; Lucknow has reported a recent uptick amid sanitation concerns; and Nagpur's larval surveys show significant household breeding. Household vigilance is the most reliable defence.
Note: City counts and civic responses are dynamic during monsoon; readers should also follow their local municipal advisories for the latest locality-specific updates.
Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.
