Viliuisk Encephalomyelitis
Encyclopedia
Viliuisk Encephalomyelitis (VE) is a fatal progressive neurological disorder
found only in the Sakha
(Iakut/Yakut
) population of central Siberia
. About 15 new cases are reported each year. VE is a very rare disease and little research has been conducted. The causative agents, origin of the disease, and involved candidate genes are currently unknown, but much research has been done in pursuit of the answers.
Those inflicted with the disease survive for a period of only a few months to several years. VE follows three main courses of infection: an acute form, a sub-acute form subsiding into a progressive
form, and a chronic
form. Initially, the infected
patients experience symptoms such as: severe headaches, delirium
, lethargy, meningism
, bradykinesia, and incoordination
. A small percentage of patients die during the acute phase as result of a severe coma
. In all cases the disease is fatal.
individuals have been infected
with VE. Viliuisk Encephalomyelitis is classified as a progressive neurological disorder
that ultimately ends in the death of the infected individual. The disease has three distinguishable phases: The acute form, the progressive form, and the chronic form.
The acute form is the most rapid and most violent of all the stages. It begins with the characteristic rigidity
of the muscles, accompanied by slurred speech, severe headaches, and exaggeration of cold-like symptoms
. Patients usually die within weeks of the initial symptoms. Routine post-mortem examinations yield: severe inflammation
of the brain lining, clusters of dead cells
and tissue
, and largely increased amounts of macrophages and lymphocytes.
The progressive form is the most common case. Patients initially experience acute-like symptoms which are not as severe, and subside within a few weeks. Following the sub-acute phase, the patients experience a few mild symptoms including some behavioral changes, incoordination, and difficulty in speech. Eventually the disease developed fully and those infected were stricken with the characteristic symptoms of rigidity
, slurred speech, and deterioration of cognitive functions
. Ultimately, brain function depreciates rapidly resulting in death.
Many patients who undergo the chronic form claim never to have had an acute attack. These patients endure varying measures of impairment and suffer mental deterioration for the remainder of their lives. Usually they live to be very old and succumb to other diseases.
In almost all cases there are changes characteristic of VE. Early onset shows an increased number of lymphocytes and increased protein
concentration — which reduces over many years. These factors help neurologists determine the form of VE based on progression. The trademark changes in the brain include: thickened inflamed
meninges
, necrotic cortical
lesions, increased number of lymphocytes, and neuron
al death..
, clinical, and neurological studies that have been conducted. Recent Studies show Horizontal Disease Transmission
, or the transmission of a disease from one individual to another of the same generation. It appears that VE is an infectious disease
; however, the incubation period
would have to be very extensive(in excess of 5 years). Many infected individuals attribute the initial symptoms as a result of a plunge in frigid waters. As of yet, no causative agent has been found in blood, spinal fluid
, or brain tissue
.
populations of northern Siberia. The disease had its debut through its first Iakut diagnosis a little over a century ago in villages of the Viuli region of Siberia. Not until after World War II did the Yakut people become aware of this mysterious killer. The locals and Northern Evenkis
referred to this illness as “Bokhoror” or “the stiffness” because of the typical rigidity
of the limbs those infected individuals experienced. Viliuisk Encephalomyelitis is currently isolated in the Iakut
(Sakha) populations of Siberia, Russia. However, extensive migration
might allow the disease to become a continental epidemic
as it has already spread the infection
radius
many miles since its induction in the early 1900s.
Fifty years ago it was believed that the Iakut
people had extremely degraded immune systems as result of malnourishment
and starvation from the World War. It was believed that this disease was docile and those with healthy immune systems could easily fight it off. This inclination appeared to be accurate until a case of a single Caucasian Russian woman. Supposedly, she infected herself as a means to end her own life. She injected herself with cerebrospinal fluid of a victim of VE, and died as a result of it. This is the first and only reported infection and death of a Caucasian.
Neurological disorder
A neurological disorder is a disorder of the body's nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord, or in the nerves leading to or from them, can result in symptoms such as paralysis, muscle weakness, poor coordination, loss of sensation, seizures,...
found only in the Sakha
Yakuts
Yakuts , are a Turkic people associated with the Sakha Republic.The Yakut or Sakha language belongs to the Northern branch of the Turkic family of languages....
(Iakut/Yakut
Yakuts
Yakuts , are a Turkic people associated with the Sakha Republic.The Yakut or Sakha language belongs to the Northern branch of the Turkic family of languages....
) population of central Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
. About 15 new cases are reported each year. VE is a very rare disease and little research has been conducted. The causative agents, origin of the disease, and involved candidate genes are currently unknown, but much research has been done in pursuit of the answers.
Those inflicted with the disease survive for a period of only a few months to several years. VE follows three main courses of infection: an acute form, a sub-acute form subsiding into a progressive
Progressive illness
The term progressive illness describes the course of an illness that gradually progresses and changes mode, generally to the worse. In contrast, non-progressive or chronic illnesses are relatively constant.-Examples:...
form, and a chronic
Chronic (medicine)
A chronic disease is a disease or other human health condition that is persistent or long-lasting in nature. The term chronic is usually applied when the course of the disease lasts for more than three months. Common chronic diseases include asthma, cancer, diabetes and HIV/AIDS.In medicine, the...
form. Initially, the infected
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
patients experience symptoms such as: severe headaches, delirium
Delirium
Delirium or acute confusional state is a common and severe neuropsychiatric syndrome with core features of acute onset and fluctuating course, attentional deficits and generalized severe disorganization of behavior...
, lethargy, meningism
Meningism
Meningism is the triad of nuchal rigidity , photophobia and headache. It is a sign of irritation of the meninges, such as seen in meningitis, subarachnoid hemorrhages and various other diseases...
, bradykinesia, and incoordination
Kinesiology
Kinesiology, also known as human kinetics is the scientific study of human movement. Kinesiology addresses physiological, mechanical, and psychological mechanisms. Applications of kinesiology to human health include: biomechanics and orthopedics, rehabilitation, such as physical and occupational...
. A small percentage of patients die during the acute phase as result of a severe coma
Coma
In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...
. In all cases the disease is fatal.
Cases and Pathophysiology
As of 2007, fewer than 500 YakutYakuts
Yakuts , are a Turkic people associated with the Sakha Republic.The Yakut or Sakha language belongs to the Northern branch of the Turkic family of languages....
individuals have been infected
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
with VE. Viliuisk Encephalomyelitis is classified as a progressive neurological disorder
Neurological disorder
A neurological disorder is a disorder of the body's nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord, or in the nerves leading to or from them, can result in symptoms such as paralysis, muscle weakness, poor coordination, loss of sensation, seizures,...
that ultimately ends in the death of the infected individual. The disease has three distinguishable phases: The acute form, the progressive form, and the chronic form.
The acute form is the most rapid and most violent of all the stages. It begins with the characteristic rigidity
Rigidity
Rigid or rigidity may refer to:*Stiffness, the property of a solid body to resist deformation, which is sometimes referred to as rigidity*Structural rigidity, a mathematical theory of the stiffness of ensembles of rigid objects connected by hinges...
of the muscles, accompanied by slurred speech, severe headaches, and exaggeration of cold-like symptoms
Common cold
The common cold is a viral infectious disease of the upper respiratory system, caused primarily by rhinoviruses and coronaviruses. Common symptoms include a cough, sore throat, runny nose, and fever...
. Patients usually die within weeks of the initial symptoms. Routine post-mortem examinations yield: severe inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
of the brain lining, clusters of dead cells
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
and tissue
Tissue (biology)
Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
, and largely increased amounts of macrophages and lymphocytes.
The progressive form is the most common case. Patients initially experience acute-like symptoms which are not as severe, and subside within a few weeks. Following the sub-acute phase, the patients experience a few mild symptoms including some behavioral changes, incoordination, and difficulty in speech. Eventually the disease developed fully and those infected were stricken with the characteristic symptoms of rigidity
Rigidity
Rigid or rigidity may refer to:*Stiffness, the property of a solid body to resist deformation, which is sometimes referred to as rigidity*Structural rigidity, a mathematical theory of the stiffness of ensembles of rigid objects connected by hinges...
, slurred speech, and deterioration of cognitive functions
Cognitive functions
In some forms of psychological testing, particularly those related to the Myers-Briggs Type Indicator, the cognitive functions are defined as different ways of perceiving and judging the world...
. Ultimately, brain function depreciates rapidly resulting in death.
Many patients who undergo the chronic form claim never to have had an acute attack. These patients endure varying measures of impairment and suffer mental deterioration for the remainder of their lives. Usually they live to be very old and succumb to other diseases.
In almost all cases there are changes characteristic of VE. Early onset shows an increased number of lymphocytes and increased protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
concentration — which reduces over many years. These factors help neurologists determine the form of VE based on progression. The trademark changes in the brain include: thickened inflamed
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
meninges
Meninges
The meninges is the system of membranes which envelopes the central nervous system. The meninges consist of three layers: the dura mater, the arachnoid mater, and the pia mater. The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system.-Dura...
, necrotic cortical
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
lesions, increased number of lymphocytes, and neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
al death..
Disease Transmission and Nomenclature
Currently the mechanism of spread and infection is unknown despite the tedious epidemiologicalEpidemiology
Epidemiology is the study of health-event, health-characteristic, or health-determinant patterns in a population. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive...
, clinical, and neurological studies that have been conducted. Recent Studies show Horizontal Disease Transmission
Horizontal disease transmission
Horizontal Disease Transmission is the transmission of an infectious disease or pathogen from one individual to another in the same generation. Horizontal transmission can occur by either direct contact , or indirect contact .-External links:**...
, or the transmission of a disease from one individual to another of the same generation. It appears that VE is an infectious disease
Infectious disease
Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...
; however, the incubation period
Incubation period
Incubation period is the time elapsed between exposure to a pathogenic organism, a chemical or radiation, and when symptoms and signs are first apparent...
would have to be very extensive(in excess of 5 years). Many infected individuals attribute the initial symptoms as a result of a plunge in frigid waters. As of yet, no causative agent has been found in blood, spinal fluid
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
, or brain tissue
Tissue (biology)
Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
.
History
Research has concluded that VE has been present in the Viuli valley for many centuries among the EvenkiEvenks
The Evenks are a Tungusic people of Northern Asia. In Russia, the Evenks are recognized as one of the Indigenous peoples of the Russian North, with a population of 35,527...
populations of northern Siberia. The disease had its debut through its first Iakut diagnosis a little over a century ago in villages of the Viuli region of Siberia. Not until after World War II did the Yakut people become aware of this mysterious killer. The locals and Northern Evenkis
Evenks
The Evenks are a Tungusic people of Northern Asia. In Russia, the Evenks are recognized as one of the Indigenous peoples of the Russian North, with a population of 35,527...
referred to this illness as “Bokhoror” or “the stiffness” because of the typical rigidity
Rigidity
Rigid or rigidity may refer to:*Stiffness, the property of a solid body to resist deformation, which is sometimes referred to as rigidity*Structural rigidity, a mathematical theory of the stiffness of ensembles of rigid objects connected by hinges...
of the limbs those infected individuals experienced. Viliuisk Encephalomyelitis is currently isolated in the Iakut
Yakut
Yakut may refer to:* Yakuts, the Turkic people associated with the Sakha Republic* Yakut language, a Turkic language also known as Sakha.* Ruby in Turkish language* Yakut , a breed from Russia*Yakut Pony, horse breed from Siberia, Russia...
(Sakha) populations of Siberia, Russia. However, extensive migration
Human migration
Human migration is physical movement by humans from one area to another, sometimes over long distances or in large groups. Historically this movement was nomadic, often causing significant conflict with the indigenous population and their displacement or cultural assimilation. Only a few nomadic...
might allow the disease to become a continental epidemic
Epidemic
In epidemiology, an epidemic , occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected based on recent experience...
as it has already spread the infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...
many miles since its induction in the early 1900s.
Fifty years ago it was believed that the Iakut
Yakut
Yakut may refer to:* Yakuts, the Turkic people associated with the Sakha Republic* Yakut language, a Turkic language also known as Sakha.* Ruby in Turkish language* Yakut , a breed from Russia*Yakut Pony, horse breed from Siberia, Russia...
people had extremely degraded immune systems as result of malnourishment
Malnutrition
Malnutrition is the condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess , or in the wrong proportions....
and starvation from the World War. It was believed that this disease was docile and those with healthy immune systems could easily fight it off. This inclination appeared to be accurate until a case of a single Caucasian Russian woman. Supposedly, she infected herself as a means to end her own life. She injected herself with cerebrospinal fluid of a victim of VE, and died as a result of it. This is the first and only reported infection and death of a Caucasian.