Study Maps Antibiotic Resistance Across Open Drains in Hyderabad

Hyderabad: Scientists from the Tata Institute for Genetics and Society (TIGS) and the city-based Centre for Cellular and Molecular Biology (CCMB) have analysed wastewater from 17 locations across Hyderabad to understand how antimicrobial resistance (AMR) is spreading in the city.

Using metagenomic sequencing of open drains, rivers and lakes, they detected 89 pathogens carrying resistance genes.

Marking AMR Week, the study found that resistance to macrolides was the most common, followed by aminoglycosides, tetracyclines and beta-lactams. Researchers also identified mutations in the 23S rRNA gene — a mechanism that helps bacteria evade macrolide antibiotics commonly used for respiratory and stomach infections.

Similar resistance patterns were observed at almost all sampling sites, indicating that AMR is now widespread across the city’s environment, said Dr Rakesh Mishra, director, Tata Institute for Genetics and Society (TIGS).

The 17 sampling sites in this study include 10 open drains, four rivers and three lakes, all of which receive untreated sewage from households, industries and farming activities in the city.

Most of Hyderabad’s sewage enters open drains, which also carry waste from households, livestock, farms, hospitals and small industries. This mix creates conditions where bacteria from humans and animals interact and exchange resistance traits.

The study noted that AMR signatures were shared across human, bird and livestock pathogens, pointing to a broader One Health impact.

The researchers also observed a correlation between the number of hospitals within two kilometres of a sampling site and the diversity of resistance genes present, suggesting that antibiotic use in healthcare settings may be contributing to AMR in surrounding areas.

The surveillance detected pathogens such as E. coli, H. pylori, Campylobacter jejuni, Neisseria gonorrhoeae, Pseudomonas aeruginosa and Klebsiella pneumoniae, many of which are listed by the WHO as priority organisms. Only Haemophilus influenzae was absent from the wastewater samples.

Hyderabad generates about 6,246 million litres of sewage daily, of which less than half is treated; the rest flows into open nalas and water bodies. The researchers say that monitoring wastewater offers a city-wide picture of AMR, capturing infections from carriers, undiagnosed cases and environmental sources that clinical data often misses.

“We suggest that this approach can be used in other developing countries to map resistance patterns, identify drug classes losing effectiveness and guide the development of new treatments. Treating open nalas and improving wastewater management would help reduce the spread of resistant bacteria,” said Dr Rakesh Mishra.