a rare chronic progressive encephalitis caused by the measles virus and occurring primarily in children and young adults; death usually occurs within three years; characterized by primary measles infection before the age of two years

子供や若年成人に主に発生する麻疹ウイルスによって引き起こされる希少な慢性進行性脳炎。死亡は通常3年以内に発生し、2歳未満の麻疹感染が特徴。