Chennai: In a global first, scientists from IIT Madras, the University of Wisconsin-Madison, and the University of Texas at Austin have conducted the longest DNA-based monitoring of a natural environment, analyzing viral communities in freshwater lakes over 20 years.

Published in Nature Microbiology, the study reconstructed 1.3 million viral genomes from 465 samples collected in Madison, Wisconsin.

The research highlights the vital and often misunderstood role of viruses in nature. Far from being purely harmful, many viruses—especially bacteriophages or “phages”—help regulate bacterial populations, making them potential tools in combating antibiotic-resistant infections through phage therapy.

Led by Dr. Karthik Anantharaman, Visiting Professor at IIT Madras, the study used advanced machine learning techniques to analyze metagenomic data, revealing how viruses evolve, cycle seasonally, and adapt to environmental changes. Key findings include the discovery of 578 viral genes aiding processes like photosynthesis and methane usage, and the influence of pollutants like carbon and ammonium on viral populations.

Dr. Anantharaman emphasized the importance of long-term viral monitoring in predicting pandemics and understanding ecosystem dynamics. Prof. Karthik Raman of IIT Madras noted that viruses, like apex predators, help maintain ecological balance.

This pioneering work opens new avenues for using viruses in ecosystem restoration and water resource management.