National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Encephalitis lethargica


Other Names:
Von Economo’s disease; Von Economo encephalitis
Categories:
Encephalitis lethargica (EL) is a disease characterized by high fever, headache, double vision, delayed physical and mental response, extreme tiredness (lethargy), and sometimes coma. Patients may also experience abnormal eye movements, upper body weakness, muscle pain, tremors, neck rigidity, and behavioral changes including psychosis. A worldwide epidemic of EL occurred from 1917 to 1928 with more than one million reported cases.[1][2] Although occasional cases are reported with similar symptoms, EL epidemics have not recurred.[1] The cause of this condition is unknown, but a viral origin is suspected.[2] Treatment depends on a person's symptoms. Levodopa and other antiparkinson drugs may be effective in alleviating some symptoms.[1]
Last updated: 6/7/2016

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Encephalopathy 0001298
Sleep disturbance
Difficulty sleeping
Trouble sleeping
[ more ] 		0002360
30%-79% of people have these symptoms
Abnormal involuntary eye movements 0012547
Autoimmunity
Autoimmune disease
Autoimmune disorder
[ more ] 		0002960
Bilateral basal ganglia lesions 0007146
Diplopia
Double vision
0000651
Dyskinesia
Disorder of involuntary muscle movements
0100660
Fever 0001945
Headache
Headaches
0002315
Increased circulating antibody level 0010702
Increased CSF protein 0002922
Lethargy 0001254
Mental deterioration
Cognitive decline
Cognitive decline, progressive
Intellectual deterioration
Progressive cognitive decline
[ more ] 		0001268
Myalgia
Muscle ache
Muscle pain
[ more ] 		0003326
Parkinsonism 0001300
Pharyngitis 0025439
Recurrent viral infections 0004429
Tremor 0001337
Upper limb muscle weakness
Decreased arm strength
Weak arm
[ more ] 		0003484
5%-29% of people have these symptoms
Bowel incontinence
Loss of bowel control
0002607
Bradycardia
Slow heartbeats
0001662
Coma 0001259
Hyperventilation
Rapid breathing
0002883
Limb pain 0009763
Photophobia
Extreme sensitivity of the eyes to light
Light hypersensitivity
[ more ] 		0000613
Psychosis 0000709
Seizure 0001250
Stiff neck
Neck stiffness
0025258
Urinary incontinence
Loss of bladder control
0000020
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Last updated: 7/1/2020

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Encephalitis lethargica. Click on the link to view a sample search on this topic.

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  • When I was about 8-years-old, I was hospitalized due to encephalitis lethargica. I was extremely ill and it took me a long time to recover. Last May, I was diagnosed with a benign meningioma. Could my childhood illness be related to the development of my tumor? Are there any documented cases of meningioma in other survivors of encephalitis lethargica? See answer


  1. NINDS Encephalitis Lethargica Information Page. National Institute of Neurological Disorders and Stroke Website. February 12, 2007; http://www.ninds.nih.gov/disorders/encephalitis_lethargica/encephalitis_lethargica.htm. Accessed 6/7/2016.
  2. Dennis Tappea, David E. Alquezar-Planas. Medical and molecular perspectives into a forgotten epidemic: Encephalitis lethargica, viruses, and high-throughput sequencing. Journal of Clinical Virology. October 2014; 61(2):189-195. https://www.ncbi.nlm.nih.gov/pubmed/25129855.