I Need A Suggestion. My Cook's Son Is Having Fever

I need a suggestion. My cook's son is having fever in brain for last 6 days. Initially hewas having fits too. max of two fits in a day but since last 48 hours no convulsions or fits came. but he is still in ICU. Doctors suspected that it is either a bacterial or vairal infection but the CSF report is also negative. His body vitals are also working fine. but they told dat dere z fever in brain and the brain is swollen. can u please guide that wat it could be. Is it life threatening? He is only one year old.