Climate change may worsen waterborne diseases: Study

A new study has sounded the alarm that climate change could reverse decades of progress in reducing waterborne diseases in India. The research, which reviews global data alongside Indian health trends, indicates that rising temperatures, erratic monsoons, and flooding are creating conditions that allow pathogens to thrive.

Scientists warn that diseases like cholera, typhoid, and hepatitis A — long considered manageable — could see a resurgence if warming continues unchecked. The study, conducted by a team of environmental health experts, was published earlier this week.

How warming fuels waterborne outbreaks

Higher temperatures accelerate the growth of bacteria in water sources. Vibrio cholerae, the bacterium that causes cholera, multiplies faster in warmer water. Similarly, typhoid-causing Salmonella typhi survives longer in warmer environments.

Extreme weather events, such as floods and cyclones, overwhelm sewage systems and contaminate drinking water supplies. In India, where millions rely on untreated groundwater or municipal supplies that are often compromised, the risk is particularly acute.

The study notes that districts already experiencing water stress — such as parts of Uttar Pradesh, Bihar, and West Bengal — are most vulnerable.

Progress under threat

India has made notable gains against waterborne diseases in recent decades. Improved sanitation, vaccination drives, and better access to clean water have reduced mortality. But the study warns that climate change could undo this progress.

Data from the Indian Council of Medical Research shows that diarrheal diseases still kill over 1 lakh children under five every year. Even a small uptick in cases due to climate factors could overwhelm already strained healthcare systems in rural areas.

The researchers point out that current public health strategies do not fully account for climate variability. Disease surveillance systems are not designed to predict outbreaks based on weather patterns.

Dengue and flu no longer seasonal

Parallel research has highlighted that diseases like dengue and influenza are no longer confined to specific seasons in India. A separate report by NDTV noted that erratic temperatures and humidity changes are extending transmission windows.

Dengue cases are now reported year-round in several states, including Delhi and Karnataka. This shift complicates response planning, as health infrastructure is typically scaled up only during known peak seasons.

The convergence of climate-driven changes — waterborne and vector-borne diseases alike — demands a more integrated approach to public health.

What needs to change

The study recommends strengthening water quality monitoring at the local level. Real-time data on temperature, rainfall, and bacterial contamination could help issue early warnings.

Investment in climate-resilient water infrastructure is critical. This includes better drainage systems in urban areas, flood-proof wells in rural zones, and household-level water treatment programs.

Health workers, particularly ASHA and anganwadi workers, need training to recognize climate-linked disease patterns. The study also calls for updating treatment protocols to account for potential antibiotic resistance, which can worsen waterborne infections.

Researchers emphasize that reducing greenhouse gas emissions is the only long-term solution. But in the interim, adaptive measures can save lives.

India's National Action Plan on Climate Change includes a health component, but implementation across states remains uneven. The study urges the Ministry of Health to coordinate with the Ministry of Jal Shakti and the India Meteorological Department for a unified response.

Experts say the window for action is narrowing. With each degree of warming, the burden of waterborne diseases will likely grow. The next few years will be critical in determining whether India can safeguard the health gains of the past two decades against the emerging threat of climate change.