Von Economo's disease is a rare brain illness that can cause extreme sleepiness, fever, headache, and changes in movement or behavior. The early symptoms of Von Economo's disease may look like a severe infection at first, but some people later develop stiffness, tremor, or trouble speaking. It may help to know that doctors have studied this condition for decades, although it is still uncommon today. Symptoms can last for weeks during the first illness, and some people are left with long-term movement or thinking problems. Treatment is supportive and may include hospital care, medicines for symptoms, and rehabilitation, and the outlook can range from recovery to severe disability or death.
How many people live with Von economo's disease?
Von Economo's disease, also called encephalitis lethargica, does not have a reliable current worldwide or U.S. count. Modern cases are very rare, and global and U.S. prevalence estimates are not consistently reported by a single authoritative source because most recent reports are isolated case reports rather than numbers from a standard registry.
Overview
Von economo's diseaseSymptoms
Von Economo's disease often causes extreme sleepiness, fever, headache, and trouble moving. Some people develop eye movement changes, weakness, or shaking. Early symptoms of Von Economo's disease can look like a bad flu with unusual drowsiness.
Outlook and prognosis
Von Economo's disease can vary widely, from gradual improvement to lasting problems with movement, sleep, mood, or thinking. Early supportive care and rehab can help daily function, but some people develop long-term parkinsonism or need ongoing help.
Causes and risk factors
Von Economo's disease has no proven single cause. Many experts suspect an abnormal immune response, sometimes after an infection, in people who may already have a biological susceptibility. Clear lifestyle or environmental risk factors have not been established.
Genetic influences
Genetics are not thought to play a major role in Von Economo's disease. Most cases have not been linked to inherited gene changes, and any genetic influence, if present, appears limited and still uncertain.
Diagnosis
Von Economo's disease is diagnosed mainly from symptoms, medical history, and a neurologic exam. Doctors often use brain imaging, spinal fluid tests, and blood tests to rule out other causes. There is no single definitive test for diagnosis of Von Economo's disease.
Treatment and drugs
Von Economo's disease is treated with hospital care, medicines to control inflammation or infection when suspected, and support for sleep, movement, breathing, and nutrition. Some people also need rehabilitation and treatment for Parkinson-like symptoms.
Symptoms
Von Economo's disease can begin with a mix of flu-like illness and sudden changes in sleep, movement, or behavior. Many people feel unusually sleepy or, less often, unable to sleep, and they may also notice vision problems or slowed movements. Symptoms vary from person to person and can change over time.
Overwhelming daytime sleepiness is one of the best-known symptoms of Von Economo's disease. Some people sleep for long stretches or drift off during meals, conversations, or other routine tasks.
Not everyone becomes sleepy. Some people have severe insomnia, restless nights, or a flipped sleep-wake schedule instead.
Fever, headache, sore throat, and a general sick feeling can be early symptoms of Von Economo's disease. These often show up near the start, sometimes before the nerve-related symptoms become clear.
Double vision, blurred vision, drooping eyelids, or trouble moving the eyes can happen. In daily life, this may make reading, driving, or looking from side to side harder.
How people usually first notice Von economo's disease?
People usually first notice Von Economo's disease when a flu-like illness is followed by unusual sleepiness, profound fatigue, and a sense that something is suddenly off with thinking or behavior. Early warning signs can also include fever, headache, double vision, eye movement problems, or stiffness and slowness that make the face seem less expressive and the body harder to move. Because these symptoms can unfold quickly and affect both the brain and movement, many living with this condition first come to medical attention when extreme drowsiness, confusion, or sudden changes in alertness become impossible to ignore.
Types of Von economo's disease
Von Economo's disease can look quite different from one person to another, which is why doctors often describe a few main clinical forms rather than expecting the same pattern in everyone. These types of Von Economo's disease are based on which problems stand out most, such as extreme sleepiness, unusual movements, or stiffness and slowed movement. Symptoms don’t always look the same for everyone.
Sleepy form
This form is marked by overwhelming drowsiness, long periods of sleep, and trouble staying alert during the day. Many living with Von Economo's disease in this group may also have drooping eyelids, double vision, or other eye-movement problems.
Hyperactive form
This type tends to cause restlessness, agitation, and abnormal movements that can seem fidgety, jerky, or hard to control. Some may also have trouble sleeping, emotional changes, or bursts of unusual behavior rather than severe sleepiness.
Akinetic form
This form is linked to marked slowing, muscle stiffness, and difficulty starting movement, similar to parkinsonism. For many, this can mean a face that looks less expressive, a soft voice, and trouble walking or carrying out daily tasks.
Can I slow down the onset of symptoms?
At this time, there is no proven way to meaningfully slow or delay the start of symptoms in Von Economo's disease, a rare illness that affects the brain. Healthy habits like regular sleep, physical activity, balanced meals, and routine medical care are good for overall health, but they have not been shown to prevent this condition or clearly lower the chance that symptoms will begin. Research is still looking at possible infection-related and body-defense-system triggers, so the most helpful step is to seek medical care early if unusual sleepiness, behavior changes, or changes in how someone moves start to appear, even though that cannot guarantee a different outcome.
What genetics can tell you about symptoms
For people living with Von Economo's disease, genetics does not currently give a clear, reliable way to predict which symptoms will happen, how severe they will be, or when they will start. This condition is generally not thought of as a classic inherited disorder, and most experts believe genes, if they play any role at all, are likely only one small part of a much more complex picture. In practice, that means symptoms can vary widely from one person to another, and doctors do not use genetic testing to forecast the course of the illness.
Causes and risk factors
If you are wondering what causes Von Economo's disease, doctors still do not know for sure. Researchers think Von Economo's disease may involve brain inflammation after an infection, and an abnormal immune response is one of the main ideas being studied. That said, risk is only part of the story. There is no clear proof that lifestyle habits cause Von Economo's disease, and no single inherited gene change has been shown to be the main cause. Because this illness is very rare, firm risk factors are hard to define, but infections, immune system changes, and possibly genetic susceptibility are the leading areas of research.
What are the most common causes or risk factors?
The exact cause of Von Economo's disease, also called encephalitis lethargica, is still unknown. The strongest leading ideas are that it may be triggered by an infection and then worsened by the body's immune system mistakenly causing inflammation in the brain, but no single virus or bacteria has been proven to cause it. Because it is very rare and not well understood, there are no clearly confirmed inherited risk factors and no common lifestyle risks that have been firmly linked to it.
Environmental and biological risk factors
Von Economo's disease, also called encephalitis lethargica, is a rare brain illness first recognized in large outbreaks in the early 1900s. Its exact cause is still uncertain, so the risk factors for Von Economo's disease are not as clearly mapped as they are for many other conditions. Researchers are still exploring how outside influences interact with our inner biology.
Many experts think an infection may act as a trigger, although no single germ has been proven to cause Von Economo's disease. Risk may be higher during outbreaks or after close exposure to people with a similar illness.
Some researchers think the illness may develop when the immune system reacts abnormally after an infection and inflames parts of the brain. Two people with the same exposure can react very differently—biology shapes the response.
Historically, most cases appeared in community outbreaks, which suggests that shared environmental exposure may matter. Crowded indoor settings can make a suspected infectious trigger easier to spread, although this has not been confirmed in every case.
Historical reports suggest Von Economo's disease affected children, teenagers, and young adults more often during some outbreaks, though many ages were represented. This means age may influence risk, but it is not a reliable predictor on its own.
Genetic risk factors
Current evidence does not show a clear inherited cause for Von Economo's disease. Most people who develop it do not have a known family history, and no single gene has been proven to cause it. Because the condition is so rare and still not fully understood, the genetic risk factors for Von Economo's disease remain uncertain. At this point, doctors do not treat it as a condition with a well-established hereditary pattern.
Single gene: No single gene has been confirmed as a cause of Von Economo's disease. There is no known inherited gene change that reliably explains why it develops.
Family history: Von Economo's disease is not known to run strongly in families. Many people with it have no close relative with the same illness.
Hereditary pattern: Most reported cases happen without a clear inherited pattern. This makes a direct genetic risk much harder to identify.
Genetic testing: Routine genetic testing is not usually used to predict or confirm Von Economo's disease. Right now, testing does not have a proven role because no causative gene has been established.
Lifestyle risk factors
For Von Economo's disease, also called encephalitis lethargica, there are no clearly proven lifestyle risk factors known to trigger the illness. Current evidence does not show that diet, exercise, or other personal habits directly cause it. Still, some everyday habits can influence symptom burden, day-to-day functioning, and recovery, which is why people sometimes ask how lifestyle affects Von Economo's disease.
Irregular or poor-quality sleep can worsen daytime sleepiness, attention problems, and mental slowing in people with Von Economo's disease. A steady sleep schedule may help reduce added fatigue and make symptoms easier to manage.
Alcohol can intensify drowsiness, impair balance, and worsen thinking problems that may already be present with Von Economo's disease. Heavy use can also interfere with rehabilitation, safe mobility, and medication adherence.
Sedating or stimulating drugs may aggravate confusion, sleep disruption, movement symptoms, or behavioral changes linked to Von Economo's disease. Avoiding these substances can help clinicians judge the true pattern of symptoms and response to treatment.
Too little movement can lead to deconditioning, muscle stiffness, and reduced mobility, which may be especially problematic if Von Economo's disease causes slowing or parkinsonian features. Gentle, supervised activity can help preserve strength, flexibility, and daily function.
Risk prevention
There is no known, proven way to prevent Von Economo's disease itself, because its exact cause is still not fully understood. For many, this can mean prevention focuses on lowering possible triggers, reducing complications, and getting medical care quickly if concerning symptoms appear. Prevention is about lowering risk, not eliminating it completely.
Because Von Economo's disease has long been linked to inflammation after an infection, lowering your chance of common infections may help reduce risk. Handwashing, avoiding close contact when people are clearly ill, and staying home when you are sick are simple steps that support this.
Keeping routine vaccines current can help prevent infections that may trigger serious brain inflammation in some people. This will not specifically guarantee prevention of Von Economo's disease, but it supports overall protection.
Quick treatment for high fever, severe headache, marked sleepiness, confusion, or unusual behavior may lower the chance of serious complications from brain inflammation. If possible early symptoms of Von Economo's disease appear, urgent medical assessment is important.
Wearing seat belts, using helmets when needed, and avoiding harmful drug use can reduce other causes of brain injury or inflammation that may worsen recovery. Alongside medical care, everyday habits also matter.
Can you prevent Von economo's disease?
No, there is no proven way to prevent Von Economo's disease because doctors still do not fully understand what causes it. General steps that help lower the risk of some infections, such as good handwashing and staying up to date with routine vaccines, may support overall health, but they are not known to specifically prevent this rare brain illness.
Transmission
Von Economo's disease, also known as encephalitis lethargica, is not thought to spread easily through everyday contact. Because the exact cause is still uncertain, doctors cannot say for sure how Von Economo's disease spreads, but there is no strong evidence that it passes readily from person to person like a cold, flu, or COVID-19.
Many living with concerns about this condition want a clear answer about how infectious it is; based on what is known, Von Economo's disease is not considered a highly contagious illness. Researchers have explored possible links to past infections, but no single germ or usual pattern of transmission has been firmly proven.
When to test your genes
For Von Economo's disease, genetic testing is not routinely recommended because it is not a well-established inherited condition. Early detection depends on prompt medical evaluation of symptoms such as unusual sleepiness, movement changes, or behavior changes. If another neurologic disorder runs in your family, a genetics specialist may help decide whether broader testing makes sense.
Diagnosis
Von Economo's disease is usually diagnosed by putting together the pattern of symptoms, the exam, and test results rather than relying on one single test. People with this condition may come to medical attention because of extreme sleepiness, behavior changes, eye movement problems, or new movement symptoms that interfere with daily life. Doctors usually begin with a careful review of when symptoms started and how they have changed over time.
A detailed history helps doctors understand symptoms such as unusual sleepiness, confusion, mood or behavior changes, and movement problems. The timing of symptoms, any recent illness, and medicines or substance exposure can help narrow down the cause.
A neurologic exam checks alertness, memory, speech, eye movements, muscle tone, coordination, and walking. This can show whether the brain areas involved in movement, sleep-wake control, or behavior may be affected.
MRI is often used to look for inflammation, stroke, tumors, or other structural causes of symptoms. CT may be used first in urgent settings, but MRI usually gives a clearer picture.
Blood work helps rule out infections, autoimmune disease, thyroid problems, vitamin deficiencies, and other conditions that can look similar. In the diagnosis of Von Economo's disease, these tests are often used to exclude more common explanations.
How is Von economo's disease diagnosed?
Von Economo's disease, also called encephalitis lethargica, is diagnosed mainly from the pattern of symptoms and a doctor’s exam, especially when someone has unusual sleepiness, changes in movement, and changes in thinking or behavior. There is no single test that proves it, so doctors usually also do tests such as blood work, a brain scan, and sometimes a spinal tap, which checks the fluid around the brain and spinal cord, to rule out other causes like infection, stroke, or brain inflammation from other conditions. Genetic testing is not usually part of diagnosing this disease.
Stages of Von economo's disease
Von Economo's disease is usually described in broad phases rather than a rigid staging system. In many living with Von Economo's disease, the course can begin with a sudden brain illness, then partly improve, and in some cases lead to longer-term movement or behavior changes. Early symptoms of Von Economo's disease can include extreme sleepiness, fever, eye movement problems, or confusion, but the pattern can vary from one person to another.
Acute phase
Symptoms often start over days to weeks with marked sleepiness, fever, headache, and changes in alertness or behavior. Some people also develop eye movement problems, muscle stiffness, or abnormal movements. This is the phase when urgent medical assessment is most important.
Recovery period
After the first illness, some symptoms may ease and daily function may partly return. Recovery can be incomplete, and some may still have tiredness, slowed thinking, or lingering neurologic problems.
Chronic phase
Months or even years later, some people develop longer-term effects, especially stiffness, slowness of movement, tremor, or changes in mood and behavior. This later pattern is often linked to post-encephalitic parkinsonism, but not everyone with Von Economo's disease goes on to this stage.
Outlook and prognosis
The outlook for Von Economo's disease is highly variable and depends on the severity of the initial illness and the long-term neurological complications that follow. During the large historical outbreaks, mortality was substantial, with many reports suggesting that roughly one-third of affected patients died in the acute phase, while others recovered only partially. Among survivors, some improved over weeks to months, but many were left with lasting problems such as parkinsonism, sleep disturbances, movement abnormalities, cognitive changes, or psychiatric symptoms that could persist for years or become permanent. In people who developed post-encephalitic parkinsonism, disability could be progressive and significantly reduce quality of life, although supportive care and symptomatic treatment may help. Because modern cases are rare and often difficult to classify with certainty, precise long-term survival estimates are limited, but prognosis is generally worse when severe brain inflammation or major neurological deficits are present.
Long-term effects
For many people, the long-term picture after Von Economo's disease depends on how severe the brain inflammation was and which parts of the brain were affected. Some recover with few lasting problems, while others develop ongoing movement, sleep, thinking, or behavior changes months or even years later. In medical terms, these are sometimes called late effects or chronic symptoms. Because Von Economo's disease is rare and much of what doctors know comes from past outbreaks, prognosis can vary widely from one person to another.
One of the best-known long-term effects of Von Economo's disease is lasting slowness, stiffness, tremor, or trouble getting movements started. In some people, this can resemble Parkinson-like symptoms and may make walking, writing, or getting dressed take much longer.
Sleep-wake problems can continue long after the early illness has passed. Many living with Von Economo's disease may feel unusually sleepy during the day, have restless nights, or find their body clock stays out of sync.
Some people have lasting problems with attention, planning, memory, or mental speed. These changes may be subtle at first, such as taking longer to follow conversations or manage familiar tasks, and can become part of the long-term effects of Von Economo's disease.
Long-term effects can involve irritability, low mood, anxiety, impulsive behavior, or personality change. For many, symptoms affect relationships, school, or work as much as the physical changes do.
How is it to live with Von economo's disease?
Living with Von Economo's disease can be profoundly disruptive because it may affect sleep, movement, energy, mood, and thinking all at once, sometimes leaving people unusually drowsy, slowed, or struggling to stay engaged with daily routines. For many living with this condition, ordinary tasks such as walking, speaking, working, or keeping a regular day-night schedule can become difficult, and some may later develop movement problems that resemble parkinsonism, with stiffness and reduced facial expression. This can also ripple outward to family and caregivers, who may need to help with safety, appointments, and daily structure while adjusting to changes in personality, alertness, or independence.
Treatment and drugs
Von Economo's disease is usually treated by managing symptoms and supporting the body, because there is no single proven cure that works for everyone. In the early, more severe phase, many people with Von Economo's disease may need hospital care for problems such as extreme sleepiness, confusion, fever, breathing trouble, or changes in heart rate and blood pressure. Treatment plans often combine several approaches, including medicines to ease movement problems, sleep changes, mood or behavior symptoms, and pain, along with fluids, nutrition, and careful monitoring. If Parkinson-like symptoms develop later, doctors may try medicines that raise dopamine, although the response can vary from person to person. Rehabilitation, including physical, occupational, and speech therapy, can also be an important part of treatment to help with walking, daily tasks, and communication.
Can you cure Von economo's disease?
No, there is no proven cure for Von Economo's disease. Treatment focuses on treating the illness early when possible and helping with lasting problems like severe sleepiness, movement trouble, pain, or mood and behavior changes, often with medicines, rehabilitation, and supportive care. Some people may improve, but treatment usually aims to manage symptoms and improve daily life rather than fully make the condition go away.
Non-drug treatment
Day-to-day life with Von Economo's disease can be shaped by sleep problems, slowed movement, changes in attention, and emotional or behavior changes that make work, school, and routines harder. Managing this condition often means combining rehab therapies and practical supports to protect function and independence. Because symptoms can vary a lot, non-drug care is usually tailored to the problems that affect daily life most.
Physical therapy helps with stiffness, balance, walking, and overall mobility. For many, this can mean practicing safer transfers, building strength, and working on posture to lower fall risk.
Occupational therapy focuses on dressing, bathing, eating, writing, and other daily tasks that may become slow or difficult. Therapists can also suggest home changes and tools that make everyday activities easier and safer.
Speech and language therapy can help if Von Economo's disease affects speech clarity, voice strength, swallowing, or thinking skills used for communication. Structured programs, like swallowing therapy or cognitive-communication exercises, can help people stay safer and more connected.
Sleep routines, light exposure, and behavior-based sleep strategies may help when sleep-wake patterns are disrupted. This can be especially useful for people dealing with early symptoms of Von Economo's disease such as unusual sleepiness or trouble staying alert during the day.
Your genes may have an impact on how drugs work for you
For people living with Von Economo's disease, medicine response usually depends more on which problems are being treated, such as sleepiness, movement trouble, or behavior changes, than on known inherited differences in their genes. At this time, there are no widely used gene-based tests that clearly guide medication choice for this condition, so treatment is usually adjusted by watching closely for benefit and side effects. In day-to-day care, this often means a doctor may start with a low dose, then slowly raise or change the medicine depending on how the person responds.
Pharmacological treatments
Treatment for Von Economo's disease is not standardized, and care usually focuses on the symptoms a person is having, such as severe sleepiness, movement problems, or psychiatric changes. Because this illness is rare and poorly understood, doctors often tailor treatment case by case, and Not everyone responds to the same medication in the same way. In reports of early symptoms of Von Economo's disease or later movement problems, medicines are chosen based on whether the main issue is inflammation, parkinsonism, agitation, or catatonia.
Levodopa, often combined with carbidopa, may be used when Von Economo's disease causes stiffness, slowness, or tremor similar to parkinsonism. It can help some people move more easily, although benefit is often limited or temporary.
Amantadine or dopamine agonists such as bromocriptine have sometimes been tried for movement symptoms or reduced alertness in Von Economo's disease. Response is variable, and side effects can include confusion, nausea, or hallucinations.
Corticosteroids such as prednisone or methylprednisolone, and sometimes intravenous immunoglobulin, may be considered if doctors suspect ongoing brain inflammation or an autoimmune process. These treatments are not proven for everyone, but they are sometimes used in selected cases.
Drugs such as risperidone, olanzapine, or haloperidol may be used short term for severe agitation, psychosis, or dangerous behavior. Because some people with Von Economo's disease already have movement problems, these medicines must be used carefully since they can worsen stiffness or slowness.
Genetic influences
When a rare brain illness changes sleep, movement, and alertness, many people look first to their family history for answers. It’s natural to ask whether family history plays a role. For people asking whether Von Economo's disease is hereditary, current evidence does not point to inheritance as the main cause: no single gene has been shown to cause Von Economo's disease, and it does not have a clear pattern of being passed from parent to child. Researchers have focused more on possible triggers such as infections and the body's immune response than on inherited gene changes, though genetics may still play a small part in how someone responds to those triggers. Because of this, genetic testing is not a routine part of diagnosing or managing Von Economo's disease, and a strong family history would be unusual.
Is Von economo's disease genetic?
Genetics are not thought to play a major role in Von Economo's disease. Most cases have not been linked to inherited gene changes, and any genetic influence, if present, appears limited and still uncertain.
Having a genetic risk is not necessarily a diagnosis
Variants in genes are a usual part of being human and are widely found across the population. Most do not directly affect health and are simply part of normal human diversity. For many genes, having a variant connected to a condition points to a possible link rather than a certain diagnosis, especially when several genes and environmental factors are involved. In some situations, though, one well-understood variant in a particular gene can be enough to confirm a diagnosis.
Pharmacogenetics—how genetics influence drug effects
For many living with Von Economo's disease, treatment is mostly about easing daily problems such as severe sleepiness, movement changes, and shifts in mood or behavior, rather than matching care to a known gene change. Because Von Economo's disease is rare and its cause is still not fully understood, there is no widely accepted genetic test that routinely tells doctors which medicine will work best. Not every difference in response is genetic, but inherited differences can affect how quickly your body breaks down some medicines, which may change the chance of side effects or how well a drug works. In practice, doctors usually choose and adjust treatment based on symptoms, age, other health conditions, and careful follow-up over time. That means how genetics affect treatment for Von Economo's disease is usually indirect, not a main guide to care. If someone has unusual reactions to several medications, a doctor may sometimes consider broader drug-response genetic testing, but this is not standard treatment for Von Economo's disease.
Interactions with other conditions
People living with Von Economo's disease may have symptoms that overlap with other brain and nervous system conditions, which can make diagnosis and day-to-day care more complicated. For example, sleepiness, movement changes, stiffness, or behavior changes can resemble Parkinson-like disorders, some autoimmune brain diseases, severe infections, or certain psychiatric conditions. Doctors call it a comorbidity when two conditions occur together, and in someone with Von Economo's disease, problems such as depression, anxiety, or complications from reduced movement can add to the overall burden of illness. This matters because one condition can sometimes mask another, so what seems like worsening fatigue or confusion may also be linked to infection, medication side effects, or another neurological problem. Many living with Von Economo's disease also need careful monitoring if they have swallowing trouble, since this can raise the risk of chest infections from food or liquid going into the airway. If there are signs that look like the early symptoms of Parkinson's disease or another brain disorder, a careful review by a neurologist can help sort out what is due to Von Economo's disease and what may be a separate condition.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
What other conditions can cause similar symptoms to Von economo's disease?
Symptoms of Von Economo's disease can look a lot like Parkinson's disease and other conditions that cause slowed movement, stiffness, and changes in facial expression. It can also be confused with other brain illnesses, including viral brain infections, swelling of the brain caused by the immune system, or sometimes a stroke, because these can also cause sleepiness, confusion, behavior changes, and trouble moving. In some people, severe sleep disorders or certain mental health conditions may seem similar at first, so doctors usually look at the full pattern of symptoms and how quickly they started.
History
In the years after World War I, doctors around the world began seeing people who had suddenly become unusually sleepy, slowed down, or unable to move and speak in their usual way. Some seemed awake but almost frozen in place; others had restless movements, eye problems, or major changes in behavior. In recent decades, awareness has grown that these reports were describing what became known medically as Von Economo's disease, or encephalitis lethargica.
The condition was described most clearly by the neurologist Constantin von Economo in 1917, during a period when large outbreaks were being recognized in Europe and elsewhere. Over the next several years, thousands of cases were reported. Many living with Von Economo's disease had an illness that began like an infection, with fever, headache, sore throat, or extreme tiredness, followed by striking brain-related symptoms. Early symptoms of Von Economo's disease could vary a lot, which made it difficult to recognize at first and easy to confuse with other neurologic or psychiatric conditions.
As doctors followed survivors over time, they noticed that some people were left with long-lasting movement problems, sleep disturbances, and changes in mood, attention, or thinking. For many, this could mean trouble returning to work, school, or everyday routines such as walking outside, holding a conversation, or getting through a meal without help. These observations shaped later understanding of post-encephalitic parkinsonism, a syndrome that can develop after the original illness.
By the mid-20th century, the large epidemic had faded, and classic cases became uncommon. Researchers have continued to debate exactly what triggered Von Economo's disease, including whether infection, immune responses, or a mix of factors played a role, but no single explanation has settled every question. Even so, the history of Von Economo's disease remains important because it helped medicine connect infections and inflammation of the brain with later movement and behavior changes, and it still guides how doctors think about rare cases that look similar today.