Rabies virus Viral Viral<unk>  can occur either as a direct effect of an acute infection, or as one of the sequelae of a latent infection. The majority of viral cases of<unk>  have an unknown cause, however the most common identifiable cause of viral<unk>  is from herpes simplex infection. Other causes of acute viral<unk>  are rabies virus, poliovirus, and measles virus. Additional possible viral causes are arboviral flavivirus (St. Louis<unk> , West Nile virus), bunyavirus (La Crosse strain), arenavirus (lymphocytic choriomeningitis virus), reovirus (Colorado tick virus), and henipavirus infections. The Powassan virus is a rare cause of<unk> . Bacterial and other It can be caused by a bacterial infection, such as bacterial meningitis, or may be a complication of a current infectious disease syphilis (secondary<unk> . Certain parasitic or protozoal infestations, such as toxoplasmosis, malaria, or primary amoebic meningoencephalitis, can also cause<unk>  in people with compromised immune systems. Lyme disease or Bartonella henselae may also cause<unk> . Other bacterial pathogens, like Mycoplasma and those causing rickettsial disease, cause inflammation of the meninges and consequently<unk> . A non-infectious cause includes acute disseminated<unk>  which is demyelinated. Limbic<unk>  Limbic<unk>  refers to inflammatory disease confined to the limbic system of the brain. The clinical presentation often includes disorientation, disinhibition, memory loss, seizures, and behavioral anomalies. MRI imaging reveals T2 hyperintensity in the structures of the medial temporal lobes, and in some cases, other limbic structures. Some cases of limbic<unk>  are of autoimmune origin. Autoimmune<unk>  Autoimmune<unk>  signs can include catatonia, psychosis, abnormal movements, and autonomic dysregulation. Antibody-mediated anti-N-methyl-D-aspartate-receptor<unk>  and Rasmussen<unk>  are examples of autoimmune<unk> . Anti-NMDA receptor<unk>  is the most common autoimmune form, and is accompanied by ovarian teratoma in 58 percent of affected women 18–45 years of age.<unk>  lethargica<unk>  lethargica is identified by high fever, headache, delayed physical response, and lethargy. Individuals can exhibit upper body weakness, muscular pains, and tremors, though the cause of<unk>  lethargica is not currently known. From 1917 to 1928, an epidemic of<unk>  lethargica occurred worldwide.
Encephalitis
Meningitis
Creutzfeldt–Jakob disease  Creutzfeldt–Jakob disease  1
Meningoencephalitis
Encephalomyelitis
Cerebritis
Seroma
Meninges