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Another cause of encephalitis under study is encephalitis believed to be caused by an autoantibody attack on subunits of brain N-methyl-d-aspartate (NMDA) glutamate receptors. The autoantibodies are termed anti-NMDA receptor antibodies, and the disease is termed NMDA receptor encephalitis, first identified in 2007.
Other viruses that can cause encephalitis include several related viruses: varicella-zoster virus (the cause of chickenpox and shingles), cytomegalovirus, Epstein-Barr virus (the most common cause of infectious mononucleosis) and human herpesvirus-6 (a cause of transient encephalitis in very young children).