India, Nov. 21 -- Research on new antibiotics have hit a wall. Bacteriophages that kill disease-causing bacteria provide an alternative treatment

Every two to three months, Ritam Das, Saroj Chaudhary and Ritu Arora - who are undergraduate and PhD students at the Acharya Narendra Dev College in South Delhi's Govindpuri - travel to some of the dirtiest corners of the city to collect soil samples.

They take samples from drains, sewage and even places where people spit. "The dirtiest sample is the best sample," says Ritam Das. But what are these "best" samples for?

It is this. The group isolates bacteriophages - viruses that can kill the bacteria - from these samples.

With these bacteriophages, Kalakoti, Das, Chaudhary and Arora, along wi...