Pilgrimages may offer clue to antibiotic resistance spread
24 July 2014 Last updated at 12:06 BST
Pilgrimages are common around the world. They are a key part of culture. But recent research has shown that there may be a hidden danger.
As more people gather, and the local infrastructure is exceeded, there is an increased risk that antibiotic resistance genes can spread between pilgrims.
Tushar Banerjee visited Rishikesh in the Upper Ganges to learn more about the work.
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