The Indian Council of Medical Research has rejected a proposal by the Ministry of Water Resources to conduct research on whether water from the Ganga river could be used to treat Covid-19 patients, PTI reported on Thursday. The top medical body said that there was not enough available evidence on the subject to begin a study.

The National Mission for Clean Ganga, an arm of the water resources ministry that deals with the rejuvenation programme for the river, had received several proposals to undertake clinical studies on the subject, unidentified officials told the news agency. The proposals were forwarded to the ICMR last month.

Officials from the ministry claimed that the proposals were discussed with the scientists of the National Environmental Engineering Research Institute, who had earlier conducted a study to understand “special properties” of the Ganga under the ‘Namami Gange’ programme.

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“At present the proposals need much scientific data, proof of concept and a strong background hypothesis,” Dr YK Gupta, who chairs the committee for Evaluation of Research Proposals at ICMR, told the news agency. “This has been conveyed to them [the National Mission for Clean Ganga].”

One of the proposals received by NMCG claimed that water from the Ganga had a “ninja virus”, which scientists call bacteriophages. Another proposal said that water from the holy river boosted immunity. The third proposal, a detailed one, sought more research on the anti-viral properties of water from the river.

The number of coronavirus cases in India rose to 52,952 on Thursday and the country recorded 1,783 fatalities, according to the figures from the Union health ministry.

Clinical trials of plasma therapy in India – a procedure involving the transfusion of blood plasma from a Covid-19 patient who has recovered to another patient who is critically ill – had ignited hopes that a treatment for the highly-infectious disease had been found. Last month, the health ministry however said that there was no evidence yet to definitively say that the procedure could be used to treat Covid-19.