Beyond identifying threats, the researchers propose wider use of wastewater-based pathogen surveillance across the country, outlining a practical path forward for public health despite infrastructural challenges. (Unsplash)A first-of-its-kind study mapping antimicrobial resistance (AMR) in urban wastewater across four Indian metros has found that bacteria, despite differing by city, are evolving similar ways to evade antibiotics—raising concerns for public health surveillance.The landmark study by researchers from the CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad, and partner institutions, published in its latest edition in the peer-reviewed journal Nature Communications, provides the first comprehensive AMR map in Indian urban wastewater.While antimicrobial resistance (AMR)—bacteria’s growing resistance to antibiotics—is killing millions of people worldwide every year, data on its local prevalence in India is largely missing, the researchers note.That, according to CCMB, is where this study comes in. “We do not know which deadly bacteria around us might be the most resistant to available antibiotics, and if they all follow similar mechanisms to become resistant. Traditional lab culture methods do not offer such details,” said Dr Vinay K Nandicoori, Director, CSIR-CCMB.Conducted between March 2022 and March 2024, the study analysed 447 samples from 19 sites across Delhi, Mumbai, Kolkata, and Chennai. The findings reveal a complex landscape—different bacteria are abundant in different cities, but they follow similar mechanisms to resist antibiotics.The researchers used a shotgun metagenomics approach to examine bacterial genes in detail, allowing them to estimate how bacteria develop resistance.According to the study, bacteria become resistant due to certain genes. These genes either help them build stronger cell walls that antibiotics cannot penetrate, enable them to metabolise or expel antibiotic molecules, or even destroy these molecules. Bacteria can share these genes not only with their offspring but also with neighbouring microbes.Story continues below this adThe study finds that microbial communities shift based on local environmental factors. For example, Klebsiella pneumoniae is more abundant in Chennai and Mumbai, while Pseudomonas aeruginosa is more prevalent in Kolkata. However, the genes conferring resistance to various antibiotics remained consistent across all four metro cities.Antibiotics belong to different chemical classes, such as tetracyclines, beta-lactams, and macrolides. The researchers found that bacteria can share resistance genes against tetracyclines and beta-lactams more easily than against macrolides.Beyond identifying threats, the researchers propose wider use of wastewater-based pathogen surveillance across the country, outlining a practical path forward for public health despite infrastructural challenges.“We have developed and validated a Standard Operating Procedure that allows for effective sample storage at 4°C for up to seven days without compromising data quality. The samples can be sent to common testing hubs, which suits resource-limited settings. A broader participation in wastewater-based surveillance will help to detect early outbreaks and track the spread of drug-resistant pathogens in real time,” said CSIR-CCMB director Dr V Nandicoori. Sreenivas Janyala is a Deputy Associate Editor at The Indian Express, where he serves as one of the most authoritative voices on the socio-political and economic landscape of Telangana and Andhra Pradesh. With a career spanning over two decades in mainstream journalism, he provides deep-dive analysis and frontline reporting on the intricate dynamics of South Indian governance. Expertise and Experience Regional Specialization: Based in Hyderabad, Sreenivas has spent more than 20 years documenting the evolution of the Telugu-speaking states. His reporting was foundational during the historic Telangana statehood movement and continues to track the post-bifurcation development of both Telangana and Andhra Pradesh. Key Coverage Beats: His extensive portfolio covers a vast spectrum of critical issues: High-Stakes Politics: Comprehensive tracking of regional powerhouses (BRS, TDP, YSRCP, and Congress), electoral shifts, and the political careers of figures like K. Chandrashekar Rao, Chandrababu Naidu, and Jagan Mohan Reddy. Internal Security & Conflict: Authoritative reporting on Left-Wing Extremism (LWE), the decline of the Maoist movement in former hotbeds, and intelligence-led investigations into regional security modules. Governance & Infrastructure: Detailed analysis of massive irrigation projects (like Kaleshwaram and Polavaram), capital city developments (Amaravati), and the implementation of state welfare schemes. Crisis & Health Reporting: Led the publication's ground-level coverage of the Covid-19 pandemic in South India and major industrial incidents, such as the Vizag gas leak. Analytical Depth: Beyond daily news, Sreenivas is known for his "Explained" pieces that demystify complex regional disputes, such as river water sharing and judicial allocations between the sister states. ... Read MoreStay updated with the latest - Click here to follow us on Instagram© The Indian Express Pvt Ltd