A team of experts visited the affected area a few days ago and collected about 70 samples after the children, aged between two and five years, died in five villages of the district in September and October.
Ten samples have been so far tested positive for the Japanese Encephalitis virus, Joint Director of the state health department, M.M. Pradhan, said.
The children who died had mild fever and swelling of eyes, noses and ears. They had other symptoms similar to those infected by Japanese Encephalitis, a mosquito-borne virus that kills thousands of children in India every year.
The investigation results of the remaining samples are expected soon, Pradhan said.
He said the affected villages house large number of pigs, the amplifying host of the virus.
There has been no report of new case from the district after the affected areas were disinfected and an awareness campaign was launched.