In Bihar, lack of clarity still prevails over the mystery disease which has claimed 72 lives of children in Muzaffarpur, East Champaran and Gopalganj districts of the state. Although initially it was suspected that the mystery ailment claiming lives was encephalitis, the National Institute of Virology in Pune has raised doubts over the claim.Health minister Ashwani Kumar Choubey told AIR that National Institute of Virology has now asked for brain tissue samples saying it would help to diagnose the disease in a better way.AIR Patna correspondent reports that meanwhile a World Health Organisation team visited the affected villages at Muzaffarpur. The team met the local people and tried to find out the cause of the mystery disease which has bewildered the states health authorities and doctors. However, no fresh case has been reported from any part of these districts in the past 24 hours. Altogether 35 patients are still undergoing treatment in different hospitals.