Even as doctors, scientists and health specialists in Bihar continue to investigate the "mysterious disease" which has claimed hundreds of lives in the last one month, the death of 18 more kids on Saturday has taken the toll from 156 to 174.

Additional Secretary (Health) R P Ojha said out of 402 children detected with symptoms of Acute Encephalitis Syndrome (AES), 82 have been admitted to different hospitals for treatment, while 156 died. The rest 164 children have been discharged after treatment.

Unofficial sources, however, put the death toll to 203.

Ever since the "mysterious disease" broke out on May 16, the blame game is on in the state. Bihar Health Minister Ashwani Choubey has charged the Centre with stalling the State's plan to spray the chemical in the susceptible districts -- Muzaffarpur and Gaya -- where the casualty list is long.

Last year too, the mysterious disease had taken a heavy toll as 85 children died in Muzaffarpur and Gaya. State doctors said that the death took place due to heat-stroke.

Another section of doctors led by former Union health minister C P Thakur had argued that it could be because of the white small germ found in litchi fruit, which is mostly cultivated near Muzaffarpur.

Lifestyle probed

But with death toll rising this year, the experts from the National Centre for Disease Control (NCDC), New Delhi, came to Bihar and probed the lifestyle and food habits of two survivors - (two children had fallen ill but survived). They have classified the disease as Acute Encephalitis Syndrome and believe that it is caused by an "infectious agent" that remains to be identified.

"We really do not know what is causing this. But what we do know is that this has a very high mortality," said Milind Gore, a senior scientist with the National Institute of Virology, Pune.