Mumbai H1N1 Cases Surge Sevenfold to 441 During Monsoon, BMC Data Shows

Mumbai recorded a sharp sevenfold increase in H1N1 cases during the monsoon season between June and August 31, 2026, alongside a rise in malaria infections, according to data released by the Brihanmumbai Municipal Corporation (BMC) Public Health Department.

The civic health data showed that H1N1 cases across the city surged to 441 during the three-month monsoon period this year, up from 62 cases reported during the corresponding period in 2025.

While H1N1 and malaria cases witnessed an upward trend, the BMC noted that several other seasonal illnesses recorded a decline. Both dengue and chikungunya cases saw a decrease during the same June-to-August timeframe.

Following the seasonal surge in infections, the civic body issued preventive health advisories for citizens across Mumbai. The BMC advised residents to wear boots while wading through floodwaters to guard against leptospirosis.

Additionally, the civic health department urged people to consume boiled water to reduce the risk of contracting gastroenteritis and other waterborne seasonal illnesses.