The Ganges is teeming with multi-drug resistant superbugs, including the deadly NDM-1 virus, and their levels peak during the annual pilgrimage season, says a new study.
Experts from UK's Newcastle University and the Indian Institute of Technology, Delhi, sampled water and sediments at seven sites along the upper Ganges and found that in May-June , when millions of pilgrims travel to Rishikesh and Haridwar , levels of resistance genes that lead to "superbugs" were about 60 times higher than other times of the year, reports Times of India on Tuesday.
The NDM-1 was first identified in New Delhi and coded by the resistant gene blaNDM-1 . Until recently, strains that carry blaNDM-1 were only found in clinical settings or hospitals but in 2008, blaNDM-1 positive strains were found in surface waters in Delhi. Since then, blaNDM-1 has been found elsewhere in the world, including new variants.
By comparing water quality of the upper Ganges in February and again in June, the team showed that levels of blaNDM-1 were 20 times higher per capita during the pilgrimage season than at other times.
Monitoring levels of other contaminants in the water, the study found overloading of waste treatment facilities was likely to blame and that in many cases, untreated sewage was going straight into the river where the pilgrims bathe.
"The bugs and their genes are carried in people's guts," said professor David Graham , an environmental engineer based at Newcastle University who has spent more than 10 years studying the environmental transmission of antibiotic resistance around the world. "If untreated wastes get into the water supply, resistance potential in the wastes can pass to the next person and spiraling increases in resistance can occur."
"This isn't a local problem - it's a global one. We studied pilgrimage areas because we suspected such locations would provide new information about resistance transmission via the environment . And it has - temporary visitors from outside the region overload local waste handling systems, which seasonally reduces water quality at the normally pristine sites," Graham said.
The team says it is important to protect people visiting and living at these sites while also making sure nothing interferes with important religious practices. They argue that preventing the spread of resistance genes that promote life-threating bacteria could be achieved by improving waste management at key pilgrimage sites.
"What humans have done by excess use of antibiotics is accelerate the rate of evolution , creating a world of resistant strains that never existed before. Through the overuse of antibiotics, contamination of drinking water and other factors, we have exponentially speeded-up the rate at which superbugs might develop. For example, when a new drug is developed , natural bacteria can rapidly adapt and become resistant ; therefore very few new drugs are in the pipeline because it simply isn't cost-effective to make them," Graham said.