Koraput: The unusually high incidents of kidney ailment at several villages of Kalimela and Podia blocks in Malkangiri district continues to baffle the state government, as the exact cause of the disease remains unknown years after the first case was reported.

Health officials said that over 30 people had succumbed to kidney ailment in the past five years, while around 100 people were suffering from the disease at several villages in the two blocks.

"Prevalence of kidney-related ailment is high, mostly among the adult males, at six to seven villages of the two blocks. Though we have conducted several medical tests, the actual reason for the ailment is yet to be known," said chief district medical officer Amarendra Nath Mohanty.

Mohanty said the disease was mostly confined to people belonging to the Bengali community.

"We had tested the water following suspicions that it could be the source. However, the report was negative," he said. Officials said the consumption of spurious liquor and vegetables with high pesticide content could also affect the kidney. However, they advocated detailed research to find out the cause.

"Recently, we have written to the government for a detailed research to ascertain the reason behind the outbreak. Though the situation is under control and the number of patients is not as high as compared to other districts, we have to be cautious," said Mohanty.

Sources also said the number of deaths could be much more as several cases went unreported.

"Over 15 people at our village have died of kidney ailments in the past few years. At least seven villagers are suffering from the ailment," said Jaga Madhi of Pedaguda village under Podia block.

Situated about 80km from the district headquarters town, the village is home to 60 families and has a population of over 260.

Activists have also demanded immediate government intervention to ascertain the reason behind the outbreak of kidney-related ailment in the blocks.

"It's high time a through research was done. The disease is not only confined to the Bengali community, but large number of people from the tribal communities are also affected," said former Nabarangpur MP Pradeep Majhi.