What are the main causes of encephalitis. How does encephalitis spread. Who is at higher risk of developing encephalitis. What are the key symptoms of encephalitis to watch for. How is encephalitis diagnosed and treated.

Understanding Encephalitis: Inflammation of the Brain

Encephalitis is a serious neurological condition characterized by inflammation of the brain. This inflammation can be caused by various factors, including infections, autoimmune disorders, and environmental exposures. When both the brain and spinal cord are affected, the condition is referred to as encephalomyelitis.

The immune system’s response to infections or other disorders affecting the central nervous system can lead to inflammation, resulting in a wide range of symptoms. In severe cases, encephalitis can cause brain damage, stroke, or even death.

Common Symptoms of Encephalitis: From Mild to Severe

Encephalitis can manifest with a variety of symptoms, ranging from mild to severe. Many individuals with encephalitis initially experience flu-like symptoms. However, as the condition progresses, more serious symptoms may develop.

Mild Symptoms of Encephalitis

• Fever
• Headache
• Fatigue
• Muscle aches
• Nausea

Severe Symptoms of Encephalitis

• Speech and hearing problems
• Double vision
• Hallucinations
• Personality changes
• Loss of consciousness
• Sensory loss in parts of the body
• Muscle weakness
• Partial paralysis in arms and legs
• Impaired judgment
• Seizures
• Memory loss

Is encephalitis particularly dangerous for infants. Yes, encephalitis can be especially concerning in infants. Parents should be vigilant for the following signs:

• Fever
• Lethargy
• Difficulty waking for feedings
• Vomiting
• Body stiffness
• Unexplained or unusual irritability
• Full or bulging fontanel (soft spot on the top of the head)

Risk Factors: Who is More Susceptible to Encephalitis?

While encephalitis can affect anyone from infants to older adults, certain groups are at higher risk of developing the condition. Understanding these risk factors is crucial for early detection and prevention.

High-Risk Groups for Encephalitis

• Individuals with weakened immune systems
• People living with HIV
• Those taking immunosuppressant drugs
• College freshmen living in dormitories (higher risk of meningococcal meningitis)
• Individuals in close contact with infected persons (household members, daycare centers, classrooms)

Can encephalitis be contagious. Yes, some forms of encephalitis are contagious and can be spread through various means of contact, including:

• Saliva
• Nasal discharge
• Feces
• Respiratory and throat secretions

Common modes of transmission include kissing, coughing, sharing drinking glasses, eating utensils, or personal items like toothbrushes, lipstick, or cigarettes.

Causes of Encephalitis: Unraveling the Complex Etiology

Encephalitis can result from a variety of causes, both infectious and non-infectious. Understanding these causes is essential for proper diagnosis and treatment.

Infectious Causes of Encephalitis

• Bacteria
• Viruses
• Fungi
• Parasites

Non-Infectious Causes of Encephalitis

• Autoimmune diseases
• Rheumatological conditions
• Certain medications

What percentage of encephalitis cases remain undiagnosed. Up to 60% of encephalitis cases remain undiagnosed, highlighting the challenges in identifying the exact cause of the condition.

Viral Causes of Encephalitis: Common Culprits

In the United States, several viruses are responsible for the majority of diagnosed encephalitis cases. Understanding these viral causes is crucial for prevention and treatment strategies.

Most Common Viral Causes of Encephalitis in the U.S.

• Herpes simplex virus types 1 and 2
• Arboviruses (e.g., West Nile Virus)
• Enteroviruses

How are arboviruses transmitted to humans. Arboviruses are typically transmitted from infected animals to humans through the bite of an infected tick, mosquito, or other blood-sucking insect.

Herpes Simplex Encephalitis (HSE): A Serious Form of Viral Encephalitis

Herpes simplex encephalitis (HSE) is a particularly severe form of encephalitis, accounting for approximately 10% of all cases. This condition requires immediate medical attention due to its potentially life-threatening nature.

Key Facts About Herpes Simplex Encephalitis

• Frequency: About two cases per million people per year
• Mortality rate: More than half of untreated cases are fatal
• Cause: 30% from initial infection, 70% from reactivation of earlier infection
• Most common causative agent: Herpes simplex virus type 1 (HSV-1)

Which age groups are most affected by HSE due to HSV-1. HSE caused by herpes simplex virus type 1 can affect any age group but is most commonly seen in individuals under 20 or over 40 years of age.

Symptoms of Herpes Simplex Encephalitis

• Headache and fever for up to five days
• Personality and behavioral changes
• Seizures
• Hallucinations
• Altered levels of consciousness

What are the potential long-term effects of HSE. HSE can cause severe brain damage, particularly in the frontal and temporal lobes. This can lead to significant behavioral, personality, memory, and speech problems in both adults and children beyond the first month of life.

Mosquito-Transmitted Viral Encephalitis: A Public Health Concern

In the United States, several forms of viral encephalitis are transmitted by mosquitoes. These mosquito-borne encephalitis types pose a significant public health concern, particularly in certain regions of the country.

Four Common Forms of Mosquito-Transmitted Viral Encephalitis in the U.S.

1. Eastern equine encephalitis (EEE)
2. Western equine encephalitis (WEE)
3. St. Louis encephalitis (SLE)
4. La Crosse encephalitis (LAC)

How do these mosquito-borne encephalitis types differ in their prevalence and severity. Each of these forms of encephalitis has distinct characteristics in terms of geographic distribution, seasonal occurrence, and severity of symptoms. For example, Eastern equine encephalitis, while rare, has a high mortality rate and can cause significant brain damage in survivors.

Diagnosis and Treatment of Encephalitis: A Multifaceted Approach

Diagnosing and treating encephalitis requires a comprehensive medical approach. Early detection and intervention are crucial for improving outcomes and reducing the risk of long-term complications.

Diagnostic Methods for Encephalitis

• Neurological examination
• Brain imaging (CT scan, MRI)
• Cerebrospinal fluid analysis
• Blood tests
• Electroencephalogram (EEG)
• Brain biopsy (in rare cases)

What is the primary goal of encephalitis treatment. The main objective of encephalitis treatment is to reduce inflammation in the brain and alleviate symptoms. Treatment approaches may include:

• Antiviral medications (for viral causes)
• Antibiotics (for bacterial causes)
• Anti-inflammatory drugs
• Anticonvulsants (for seizure control)
• Supportive care (e.g., breathing assistance, hydration)

Can encephalitis be prevented. While not all forms of encephalitis can be prevented, certain measures can reduce the risk of infection:

• Vaccination against preventable causes (e.g., measles, mumps, rubella)
• Practicing good hygiene
• Using insect repellent and protective clothing in areas with mosquito-borne diseases
• Avoiding tick-infested areas
• Seeking prompt medical attention for suspected infections

Long-Term Outlook and Recovery from Encephalitis

The prognosis for individuals with encephalitis can vary significantly depending on factors such as the cause, severity, and timeliness of treatment. While some people recover fully, others may experience long-term complications.

Potential Long-Term Effects of Encephalitis

• Cognitive impairment
• Memory problems
• Speech and language difficulties
• Behavioral changes
• Epilepsy
• Physical disabilities

What factors influence the recovery process from encephalitis. Several factors can impact an individual’s recovery from encephalitis:

• Age of the patient
• Cause of the encephalitis
• Severity of brain inflammation
• Promptness of diagnosis and treatment
• Overall health and immune status of the patient

Is ongoing support necessary for encephalitis survivors. Yes, many individuals who have recovered from encephalitis benefit from ongoing support and rehabilitation services. This may include:

• Physical therapy
• Occupational therapy
• Speech therapy
• Cognitive rehabilitation
• Psychological support
• Educational assistance for children

Research and Future Directions in Encephalitis Management

Ongoing research in the field of encephalitis aims to improve our understanding of the condition, develop more effective diagnostic tools, and enhance treatment options. Some areas of focus include:

• Development of new antiviral medications
• Improvement of diagnostic techniques for rapid identification of causative agents
• Investigation of immune-modulating therapies
• Study of long-term outcomes and rehabilitation strategies
• Research into preventive measures for various forms of encephalitis

How might advances in neuroimaging contribute to encephalitis management. Advancements in neuroimaging techniques, such as high-resolution MRI and PET scans, may allow for earlier detection of brain inflammation and more precise monitoring of treatment responses. This could lead to more targeted and effective therapies for encephalitis patients.

In conclusion, encephalitis remains a challenging neurological condition with potentially severe consequences. However, ongoing research and improvements in diagnostic and treatment approaches offer hope for better outcomes for those affected by this serious brain inflammation. Early recognition of symptoms, prompt medical attention, and comprehensive care are crucial in managing encephalitis and minimizing its long-term impact on patients’ lives.

National Institute of Neurological Disorders and Stroke

What is encephalitis?

Encephalitis is inflammation of the brain. Myelitis refers to inflammation of the spinal cord. When both the brain and the spinal cord are involved, the condition is called encephalomyelitis.

Infections and other disorders affecting the brain and spinal cord can activate the immune system, which leads to inflammation. This inflammation can produce a wide range of symptoms and, in extreme cases, cause brain damage, stroke, or even death.

Individuals with encephalitis often show mild flu-like symptoms. In more severe cases, people may experience:

• Problems with speech or hearing
• Double vision
• Hallucinations
• Personality changes
• Loss of consciousness
• Loss of sensation in some parts of the body

• Muscle weakness
• Partial paralysis in the arms and legs
• Impaired judgment
• Seizures
• Memory loss

Important signs of encephalitis to watch for in an infant include fever, lethargy, not waking for feedings, vomiting, body stiffness, unexplained/unusual irritability, and a full or bulging fontanel (the soft spot on the top of the head).

Who is more likely to get encephalitis?

Anyone—from infants to older adults—can get encephalitis. People with weakened immune systems, including those persons with HIV or those taking immunosuppressant drugs, are at increased risk.

Some forms of encephalitis are contagious and can be spread through contact with:

• Saliva
• Nasal discharge
• Feces
• Respiratory and throat secretions (often spread through kissing, coughing, or sharing drinking glasses, eating utensils, or such personal items as toothbrushes, lipstick, or cigarettes)

For example, people sharing a household, at a day care center, or in a classroom with an infected person can become infected. College students living in dormitories—in particular, college freshmen—have a higher risk of contracting meningococcal meningitis than college students overall.

Because the disease can occur suddenly and progress rapidly, anyone who is suspected of having encephalitis should immediately contact a doctor or go to the hospital.

Causes of encephalitis

Infectious causes of encephalitis include bacteria, viruses, fungi, and parasites. For some individuals, environmental exposure (such as a parasite), recent travel, or an immunocompromised state (such as HIV, diabetes, steroids, chemotherapy treatment) are important risk factors. There are also non-infectious causes such as autoimmune/rheumatological diseases and certain medications.

Up to 60 percent of cases of encephalitis remain undiagnosed. Several thousand cases are reported each year, but many more may occur since the symptoms may be mild to non-existent in most individuals.

Most diagnosed cases in the U.S. are caused by herpes simplex virus types 1 and 2, arboviruses (such as the West Nile Virus), which are transmitted from infected animals to humans through the bite of an infected tick, mosquito, or other blood-sucking insect, or enteroviruses. Lyme disease, a bacterial infection spread by tick bite, occasionally causes meningitis, and very rarely encephalitis. Rabies virus, which is transmitted by bites of rabid animals, is an extremely rare cause of human encephalitis.

Herpes simplex encephalitis (HSE) is responsible for about 10 percent of all encephalitis cases, with a frequency of about two cases per million people per year. More than half of untreated cases are fatal. About 30 percent of cases result from the initial infection with the herpes simplex virus; the majority of cases are caused by reactivation of an earlier infection. Most people acquire herpes simplex virus type 1 (the cause of cold sores or fever blisters) in childhood.

HSE due to herpes simplex virus type 1 can affect any age group but is most often seen in persons under age 20 or over age 40. This rapidly progressing disease is the single most important cause of fatal sporadic encephalitis in the country. Symptoms can include headache and fever for up to five days, followed by personality and behavioral changes, seizures, hallucinations, and altered levels of consciousness.  Brain damage in adults and in children beyond the first month of life is usually seen in the frontal lobes (leading to behavioral and personality changes) and temporal lobes (leading to memory and speech problems) and can be severe. 

Type 2 virus (genital herpes) is most often transmitted through sexual contact. Many people do not know they are infected and may not have active genital lesions. An infected mother can transmit the disease to her child at birth, through contact with genital secretions. In newborns, symptoms such as lethargy, irritability, tremors, seizures, and poor feeding generally develop between four and 11 days after delivery.

Four common forms of mosquito-transmitted viral encephalitis are seen in the United States:

1. Equine encephalitis affects horses and humans  
   • Eastern equine encephalitis also infects birds that live in freshwater swamps of the eastern U.S. seaboard and along the Gulf Coast. In humans, symptoms are seen within four days or up to two weeks following transmission and include sudden fever, general flu-like muscle pains, and headache of increasing severity, followed by coma and death in severe cases.  About half of infected individuals die from the disorder. Fewer than 10 human cases are seen annually in the United States. 
   • Western equine encephalitis is seen in farming areas in the western and central plains states. Symptoms begin within five and up to 10 days following infection. Children, particularly those under 12 months of age, are affected more severely than adults and may have permanent neurologic damage. Death occurs in about three percent of cases. 
   • Venezuelan equine encephalitis is very rare in the U.S. Children are at greatest risk of developing severe complications, while adults generally develop flu-like symptoms. Epidemics in Central and South America have killed thousands of people and left others with permanent, severe neurologic damage.
2. LaCrosse encephalitis occurs in the upper midwestern states (Illinois, Wisconsin, Indiana, Ohio, Minnesota, and Iowa) but has been reported in the southeastern and mid-Atlantic regions of the country.  Most cases are seen in children under the age of 16. Symptoms such as vomiting, headache, fever, and lethargy appear up to 10 days following infection. Severe complications include seizures, coma, and permanent neurologic damage. About 100 cases of LaCrosse encephalitis are reported each year.
3. St. Louis encephalitis is most prevalent in temperate regions of the U.S. but can occur throughout most of the country. The disease is generally milder in children than in adults, with elderly adults at highest risk of severe disease or death. Symptoms typically appear within seven days and up to 10 following infection and include headache and fever. In more severe cases, confusion and disorientation, tremors, convulsions (especially in the very young), and coma may occur.
4. West Nile encephalitis is usually transmitted by a bite from an infected mosquito but can also occur after transplantation of an infected organ or transfusions of infected blood or blood products. Symptoms are flu-like and include fever, headache, and joint pain. Some individuals may develop a skin rash and swollen lymph glands, while others may not show any symptoms. At highest risk are older adults and people with weakened immune systems.

Outside the U.S., Japanese encephalitis is one of the most common causes of encephalitis worldwide. It is widespread in Asia and transmitted by a mosquito. A vaccine is available so travelers to at-risk areas should discuss this with their healthcare provider.

Powassan encephalitis is rare but is the only well-documented tick-borne arbovirus in the U.S. and Canada. Symptoms are noticed seven to 10 days following the bite (most people do not notice tick bites) and may include headache, fever, nausea, confusion, partial paralysis, coma, and seizures.

It is also possible to develop encephalitis that has non-infectious or autoimmune causes. Some cases of encephalitis are caused by an autoimmune disorder that may in some instances be triggered by an infection (“post infectious”) or by a cancer—even one that is microscopic and cannot be found (so-called paraneoplastic neurological syndromes).  NMDA-Receptor encephalitis is a type of autoantibody-mediated encephalitis and is being increasingly recognized; it was the most documented form of non-bacterial meningitis reported in the long-term study and follow-up of participants in the California Encephalitis project. Treatment involves immunosuppression and/or tumor removal if such a cause is found.

How is encephalitis diagnosed and treated?

Diagnosing encephalitis

Following a physical exam and medical history to review activities of the past several days or weeks (such as recent exposure to insects, ticks or animals, any contact with ill persons, or recent travel; preexisting medical conditions and medications), the doctor may order various diagnostic tests to confirm the presence of infection or inflammation. Early diagnosis is vital, as symptoms can appear suddenly and escalate to brain damage, hearing and/or speech loss, blindness, or even death.

Diagnostic tests include:

• A neurological examination involves a series of physical examination tests designed to assess motor and sensory function, nerve function, hearing and speech, vision, coordination and balance, mental status, and changes in mood or behavior.
• Laboratory screening of blood, urine, and body secretions can help detect and identify brain and/or spinal cord infection and determine the presence of antibodies and foreign proteins. Such tests can also rule out metabolic conditions that may have similar symptoms.
• Analysis of the cerebrospinal fluid that surrounds and protects the brain and spinal cord can detect infections in the brain and/or spinal cord, acute and chronic inflammation, and other diseases. A small amount of cerebrospinal fluid is removed by a special needle that is inserted into the lower back and the fluid is tested to detect the presence of bacteria, blood, and viruses. The testing can also measure glucose levels (a low glucose level can be seen in bacterial or fungal meningitis) and white blood cells (elevated white blood cell counts are a sign of inflammation), as well as protein and antibody levels.

Brain imaging can reveal signs of brain inflammation, internal bleeding or hemorrhage, or other brain abnormalities. Two imaging procedures are routinely used to diagnose meningitis.

1. Computed tomography (CT)
2. Magnetic resonance imaging (MRI)

Additionally, electroencephalography (EEG) can identify abnormal brain waves by monitoring electrical activity in the brain.

Treating encephalitis

People who are suspected of having encephalitis should receive immediate, aggressive medical treatment. The disease can progress quickly and has the potential to cause severe, irreversible neurological damage.

Antiviral drugs used to treat viral encephalitis include acyclovir and ganciclovir. For most encephalitis-causing viruses, no specific treatment is available.

Autoimmune causes of encephalitis are treated with additional immunosuppressant drugs and screening for underlying tumors when appropriate. Acute disseminated encephalomyelitis, a non-infectious inflammatory brain disease mostly seen in children, is treated with steroids.

Anticonvulsants may be prescribed to stop or prevent seizures.  Corticosteroids can reduce brain swelling. Affected individuals with breathing difficulties may require artificial respiration.

Once the acute illness is under control, comprehensive rehabilitation should include cognitive rehabilitation and physical, speech, and occupational therapy.

Prevention

People should avoid sharing food, utensils, glasses, and other objects with someone who may be exposed to or have the infection. People should wash their hands often with soap and rinse under running water.

To lessen the risk of being bitten by an infected mosquito or other arthropod, people should limit outdoor activities at night, wear long-sleeved clothing when outdoors, use insect repellents that are most effective for that particular region of the country, and rid lawn and outdoor areas of free-standing pools of water (where mosquitoes like to breed). Repellants should not be overapplied, particularly on young children and especially infants, as chemicals like DEET may be absorbed through the skin.

The outlook for individuals with encephalitis generally depends on the particular infectious agent involved, the severity of the illness, and how quickly treatment is given. In most cases, people with very mild encephalitis can make a full recovery, although the process may be slow.

In more serious cases, the disease can cause hearing and/or speech loss, blindness, permanent brain and nerve damage, behavioral changes, cognitive disabilities, lack of muscle control, seizures, and memory loss. These individuals may need long-term therapy, medication, and supportive care. 

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Learn About Clinical Trials

Clinical trials are studies that allow us to learn more about disorders and improve care. They can help connect patients with new and upcoming treatment options.

How can I or my loved one help improve care for people with encephalitis?

Consider participating in a clinical trial so clinicians and scientists can learn more about encephalitis and related disorders.  Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.

All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.

For information about participating in clinical research visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with encephalitis at Clinicaltrials.gov.

Where can I find more information about encephalitis?

Information may be available from the following resources:

Centers for Disease Control and Prevention (CDC)
Phone: 800-232-4636

HHV-6 Foundation
Phone: 888-530-6726

MedlinePlus

National Institute of Allergy and Infectious Disease (NIAID)
Phone: 301-496-5717 or 866-284-4107

Learn about related topics

• Meningitis

Encephalitis – Brain, Spinal Cord, and Nerve Disorders

By

John E. Greenlee

, MD, University of Utah Health

Reviewed/Revised Mar 2022 | Modified Sep 2022

VIEW PROFESSIONAL VERSION

GET THE QUICK FACTS

Encephalitis is inflammation of the brain that occurs when a virus directly infects the brain or when a virus, vaccine, or something else triggers inflammation. The spinal cord may also be involved, resulting in a disorder called encephalomyelitis.

• People may have a fever, headache, or seizures, and they may feel sleepy, numb, or confused.

• Magnetic resonance imaging of the head and a spinal tap are usually done.

• Treatment involves relieving symptoms and sometimes using antiviral drugs.

(See also Overview of Brain Infections Overview of Brain Infections Infections of the brain can be caused by viruses, bacteria, fungi, or, occasionally, protozoa or parasites. Another group of brain disorders, called spongiform encephalopathies, are caused by… read more .)

Encephalitis is most commonly due to viruses, such as herpes simplex, herpes zoster, cytomegalovirus, or West Nile virus. It can occur in the following ways:

• A virus directly infects the brain.

• A virus that caused an infection in the past becomes reactivated and directly damages the brain.

• A virus or vaccine triggers a reaction that makes the immune system attack brain tissue (an autoimmune reaction Autoimmune Disorders An autoimmune disorder is a malfunction of the body’s immune system that causes the body to attack its own tissues. What triggers an autoimmune disorder is not known. Symptoms vary depending. .. read more ).

Sometimes bacteria cause encephalitis, usually as part of bacterial meningitis (called meningoencephalitis).

Protozoa—such as amebas, the protozoa that cause toxoplasmosis Toxoplasmosis Toxoplasmosis is infection caused by the protozoan parasite Toxoplasma gondii. Infection occurs when people unknowingly ingest toxoplasma cysts from cat feces or eat contaminated meat… read more (in people who have AIDS), and those that cause malaria Malaria Malaria is infection of red blood cells with one of five species of the protozoa Plasmodium. Malaria causes fever, chills, sweating, a general feeling of illness (malaise), and sometimes… read more —can also infect the brain and cause encephalitis.

Sometimes a brain infection, a vaccine, cancer, or another disorder triggers a misguided immune reaction, causing the immune system to attack normal cells in the brain (an autoimmune reaction Autoimmune Disorders An autoimmune disorder is a malfunction of the body’s immune system that causes the body to attack its own tissues. What triggers an autoimmune disorder is not known. Symptoms vary depending… read more ). As a result, the brain becomes inflamed. If triggered by an infection, the disorder is called postinfectious encephalitis. Brain infections due to an autoimmune reaction sometimes develop in people who have cancer—a disorder called paraneoplastic encephalitis.

Infections that can directly lead to encephalitis can occur in epidemics or occasionally as isolated cases (sporadically).

In the United States, the most common types of epidemic encephalitis are caused by one of the following:

• Enteroviruses Overview of Enterovirus Infections Enterovirus infections affect many parts of the body and may be caused by any of several different strains of enterovirus. Enterovirus infections are caused by many different viruses. Symptoms… read more (which more often cause meningitis)

• Arboviruses Overview of Arbovirus, Arenavirus, and Filovirus Infections Arbovirus, arenavirus, and filovirus are viruses that are spread from animals to people and, with some viruses, from people to people. The animal involved depends on the type of virus. Many… read more

Arboviruses are viruses transmitted to people through the bites of arthropods, usually mosquitoes, fleas, or ticks. (Arbovirus is short for arthropod-borne virus.) The viruses are transmitted to arthropods when arthropods bite infected animals or people. Many species of domestic animals and birds carry these viruses.

Epidemics occur in people only periodically—when the population of mosquitoes or infected animals increases. Epidemics tend to occur when arthropods are biting—for mosquitoes and ticks, usually during warm weather. Infection spreads from arthropod to person, not from person to person.

Many arboviruses can cause encephalitis. The different types of encephalitis that result are usually named for the place the virus was discovered or the animal species that typically carries it.

In the United States, mosquitoes spread several types of encephalitis, including the following:

• La Crosse encephalitis is caused by the La Crosse virus (also called California virus). It is most common in the Midwest but can occur anywhere in the country. This encephalitis accounts for most cases in children. Many cases are mild and undiagnosed. Fewer than 1% of infected people die from it.

• Eastern equine encephalitis occurs predominantly in the eastern United States. A few cases have occurred in the Great Lakes region. Eastern equine encephalitis affects mainly young children and people older than 55. In children younger than 1 year, it can cause severe symptoms and permanent nerve or brain damage. Over half of infected people die.

• West Nile encephalitis, once present only in Europe and Africa, first appeared in the New York City area in 1999. It has spread throughout the United States. Several species of birds can be infected with the virus when they are bitten by an infected mosquito. This encephalitis affects mainly older people. This virus also causes a milder infection called West Nile fever, which is much more common. West Nile encephalitis develops in fewer than 1% of people who develop West Nile fever. About 9% of people with West Nile encephalitis die. However, those who have only West Nile fever usually recover fully.

• St. Louis encephalitis occurs mostly in urban areas of central and southeastern states of the United States but also in western states. Infection is more common in the summer and is more likely to affect the brain in older people. Epidemics once occurred about every 10 years but are now rare.

• Western equine encephalitis can occur throughout the United States but, for unknown reasons, has largely disappeared since 1988. It can affect all age groups but is more severe and more likely to affect the brain in children younger than 1 year.

A few types of encephalitis are spread by ticks. They include

• Tick-borne encephalitis occurs in Northern Asia, Russia, and Europe. The infection usually causes a mild flu-like illness that clears up within a few days, but some people, usually those age 50 or older, develop more severe symptoms. Because many cases occur in Europe and Russia, a vaccine is available there.

• Powassan virus infection occurs mainly in Canada and in the Great Lakes region and northeastern United States. Powassan virus has also caused cases of encephalitis in Russia. The virus is similar to the one that causes tick-borne encephalitis in Europe. Powassan virus infection usually causes mild or no symptoms. However, the infection can also cause severe encephalitis with headache, vomiting, seizures, loss of coordination, speech problems, or coma. About 10% of people with severe encephalitis die. Powassan virus is spread by the deer tick, which also transmits Lyme disease. In Lyme disease, the tick must be attached for 24 to 48 hours to spread disease. In contrast, Powassan virus infection may be transmitted if an infected tick is attached for as little as 15 minutes. The vaccine that is effective against tick-borne encephalitis in Europe and Russia is not effective against the Powassan virus.

• Colorado tick fever occurs in areas of western United States and Canada that are 4,000 to 10,000 feet above sea level. Colorado tick fever causes a flu-like illness. Occasionally, people with Colorado tick fever develop meningitis or encephalitis. Colorado tick fever rarely causes death. It is rarely transmitted by blood transfusion.

Several viruses that cause encephalitis were once present in only a few parts of the world but now are spreading, probably because travel has increased. These viruses include

• Chikungunya virus

• Japanese encephalitis virus

• Venezuelan equine encephalitis

• Zika virus Zika Virus Infection Zika virus infection is a mosquito-borne viral infection that typically causes no symptoms but can cause fever, rash, joint pain, or infection of the membrane that covers the white of the eye… read more

All are spread by mosquitoes.

The Chikungunya virus was first identified in Africa but has spread to Southeast Asia, India, China, some parts of Europe, the Caribbean, and Central, South, and North America. Most people with chikungunya disease feel better within a week. However, chikungunya disease can lead to severe encephalitis and even death, especially in infants and people over age 65.

The Japanese encephalitis virus is a common cause of encephalitis in Asia and the western Pacific. In the United States, Japanese encephalitis occurs only in travelers who acquired the virus in areas of the world where the virus is common.

Venezuelan equine encephalitis occurs mainly in parts in South and Central America. The Venezuelan equine encephalitis virus caused an epidemic of encephalitis in Texas in 1971 but now rarely causes encephalitis in the United States. It occurs mainly in travelers returning from areas where the virus is common.

The Zika virus was first identified in the Zika Forest of Uganda, then spread to the South Pacific islands, then South America, Central America, the Caribbean, Mexico, and Florida. Zika infection may cause fever, joint and muscle aches, headache, and a red, bumpy rash. Having Zika virus infection during pregnancy can cause microcephaly Microcephaly Microcephaly is an abnormally small head. Often the head is small because the brain is small and abnormally developed. Microcephaly can be caused by many disorders including genetic abnormalities… read more and severe brain damage in the baby.

In the United States, the most common cause of sporadic viral encephalitis is herpes simplex virus Herpes Simplex Virus (HSV) Infections Herpes simplex virus infection causes recurring episodes of small, painful, fluid-filled blisters on the skin, mouth, lips (cold sores), eyes, or genitals. This very contagious viral infection… read more type 1, the same virus that causes cold sores. This encephalitis occurs at any time of the year and is often fatal if not treated.

Rabies Rabies Rabies is a viral infection of the brain that is transmitted by animals and that causes inflammation of the brain and spinal cord. Once the virus reaches the spinal cord and brain, rabies is… read more is a significant cause of encephalitis in developing countries and still causes a few cases of encephalitis in the United States.

Human immunodeficiency virus Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and is treated with antiretroviral medications. If untreated, it can cause… read more (HIV) causes a slowly developing brain infection, resulting in HIV-associated encephalopathy (also called HIV-associated or AIDS dementia HIV-Associated Dementia HIV-associated dementia is progressive deterioration in mental function due to infection of the brain with human immunodeficiency virus (HIV). Unlike almost all other forms of dementia, HIV-associated… read more ).

Encephalitis can result from reactivation of a virus, including

• Herpes simplex virus type 1

• Varicella zoster virus (the virus that causes chickenpox Chickenpox Chickenpox is a highly contagious viral infection with the varicella-zoster virus that causes a characteristic itchy rash, consisting of small, raised, blistered, or crusted spots. Chickenpox… read more )

• JC virus (which causes a usually fatal disorder called progressive multifocal leukoencephalopathy Progressive Multifocal Leukoencephalopathy (PML) Progressive multifocal leukoencephalopathy is a rare infection of the brain that is caused by the JC (John Cunningham) virus. People with a weakened immune system are most likely to get the… read more —common among people who have AIDS or other conditions that impair the immune system)

• The virus that causes measles (which, if reactivated, leads to a usually fatal disorder called subacute sclerosing panencephalitis Subacute Sclerosing Panencephalitis (SSPE) Subacute sclerosing panencephalitis, a progressive and usually fatal brain disorder, is a rare complication of measles that appears months or years later and causes mental deterioration, muscle… read more years after measles occurs)

Reactivation can occur long after people have the infection. A reactivated infection can severely damage the brain.

After people have certain viral infections or get certain vaccines, the body’s immune system sometimes attacks the layers of tissue that wrap around nerve fibers (called the myelin sheath Overview of Demyelinating Disorders Most nerve fibers inside and outside the brain are wrapped with many layers of tissue composed of a fat (lipoprotein) called myelin. These layers form the myelin sheath. Much like the insulation… read more ) in the brain and spinal cord—an autoimmune reaction Autoimmune Disorders An autoimmune disorder is a malfunction of the body’s immune system that causes the body to attack its own tissues. What triggers an autoimmune disorder is not known. Symptoms vary depending… read more . The attack occurs because proteins in myelin resemble those in the virus. As a result, nerve transmission becomes very slow. The resulting disorder, called acute disseminated encephalomyelitis Acute Disseminated Encephalomyelitis (ADEM) Disorders that cause demyelination and have no known cause are called primary demyelinating disorders. Demyelination is the destruction of the tissues that wrap around nerves, called the myelin… read more , resembles multiple sclerosis Multiple Sclerosis (MS) In multiple sclerosis, patches of myelin (the substance that covers most nerve fibers) and underlying nerve fibers in the brain, optic nerves, and spinal cord are damaged or destroyed. The cause… read more except that symptoms do not come and go as they do in multiple sclerosis. The viruses most often involved include enteroviruses Overview of Enterovirus Infections Enterovirus infections affect many parts of the body and may be caused by any of several different strains of enterovirus. Enterovirus infections are caused by many different viruses. Symptoms… read more , Epstein-Barr virus Infectious Mononucleosis Epstein-Barr virus causes a number of diseases, including infectious mononucleosis. The virus is spread through kissing. Symptoms vary, but the most common are extreme fatigue, fever, sore throat. .. read more , hepatitis A Hepatitis A Acute hepatitis A is inflammation of the liver that is caused by the hepatitis A virus and that lasts less than 6 months. Hepatitis A is usually spread when people ingest something that has… read more or hepatitis B Hepatitis B, Acute Acute hepatitis B is inflammation of the liver that is caused by the hepatitis B virus and that lasts from a few weeks up to 6 months. Hepatitis B is spread through contact with blood or other… read more virus, human immunodeficiency virus Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and is treated with antiretroviral medications. If untreated, it can cause… read more (HIV), and influenza viruses Influenza (Flu) Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general. .. read more . Before vaccination of children became widespread, the viruses that cause measles, rubella, chickenpox, and mumps used to be common causes of acute disseminated encephalomyelitis. This type of encephalitis can also occur in people with cancer or other autoimmune disorders.

An autoimmune encephalitis may also develop if the immune system produces antibodies that attack proteins on the surface of nerve cells called N-methyl-d-aspartate (NMDA) receptors. The resulting encephalitis is called anti-NMDA receptor encephalitis. Some evidence suggests that anti-NMDA receptor encephalitis is a more common type of encephalitis than was previously thought. It occasionally develops after encephalitis due to the herpes simplex virus, even when that encephalitis was successfully treated.

Rarely, people with COVID-19 COVID-19 COVID-19 is an acute respiratory illness that can be severe and is caused by the coronavirus named SARS-CoV-2. Symptoms of COVID-19 vary significantly. Two types of tests can be used to diagnose… read more develop what appears to be encephalitis. (COVID-19 is caused by the newly identified severe acute respiratory syndrome coronavirus, or SARS-CoV2.) This encephalitis may be caused by the virus that enters and affects the brain. But it may also be an autoimmune or a partly autoimmune reaction.

Before symptoms of encephalitis start, people may have digestive symptoms, such as nausea, vomiting, diarrhea, or abdominal pain. Or they may feel as if they are getting a cold or the flu and have cough, fever, a sore throat, a runny nose, swollen lymph nodes, and muscle aches.

Symptoms of encephalitis include

• Fever

• Headache

• Personality changes or confusion

• Seizures

• Paralysis or numbness

• Sleepiness that can progress to coma and death

People may vomit and have a stiff neck, but these symptoms tend to be less common and less severe than when caused by meningitis.

Encephalitis due to the herpes simplex virus causes headache, fever, and flu-like symptoms at first. People also have seizures, sometimes accompanied by strange smells (such as rotten eggs), vivid flashbacks, or sudden, intense emotions. As the encephalitis progresses, people become confused, have difficulty speaking and remembering, have repeated seizures, then lapse into coma.

HIV-associated encephalopathy can cause gradual personality changes, problems with coordination, and dementia.

If the spinal cord is affected, parts of the body may feel numb and weak. Which parts are affected depend on which parts of the spinal cord are affected (see figure Where Is the Spinal Cord Damaged? Where Is the Spinal Cord Damaged? ). If the infection is severe, people may lose sensation, become paralyzed, and lose control of the bladder and bowels.

Recovery from viral encephalitis may take a long time. Some people do not completely recover. The likelihood of dying depends on what the cause is and how quickly the infection is treated.

Did You Know…

Doctors suspect encephalitis based on symptoms, especially if an epidemic is in progress. Magnetic resonance imaging (MRI) and a spinal tap are usually done.

MRI can sometimes detect abnormalities in certain areas of the brain. These abnormalities may help confirm the diagnosis of encephalitis and/or suggest which virus is causing encephalitis. If MRI is not available, computed tomography (CT) may be done. MRI and CT can help doctors exclude disorders that can cause similar symptoms (such as stroke Ischemic Stroke An ischemic stroke is death of an area of brain tissue (cerebral infarction) resulting from an inadequate supply of blood and oxygen to the brain due to blockage of an artery. Ischemic stroke… read more and a brain tumor Overview of Brain Tumors A brain tumor can be a noncancerous (benign) or cancerous (malignant) growth in the brain. It may originate in the brain or have spread (metastasized) to the brain from another part of the body. .. read more ). These tests can also check for problems that can make doing a spinal tap dangerous.

A spinal tap Spinal Tap Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which… read more (lumbar puncture) is done to obtain a sample of cerebrospinal fluid, which flows through the tissues (meninges) that cover the brain and spinal cord. Normally, the spinal fluid contains very few white blood cells. But when the brain and meninges are inflamed, the number of white cells in cerebrospinal fluid increases.

To identify the virus causing encephalitis, doctors take samples of blood and cerebrospinal fluid and test them for antibodies to the virus when the person is sick and later when the person is recovering. Sometimes techniques are used to grow (culture) viruses in the cerebrospinal fluid so that they can be identified more easily. Some enteroviruses Overview of Enterovirus Infections Enterovirus infections affect many parts of the body and may be caused by any of several different strains of enterovirus. Enterovirus infections are caused by many different viruses. Symptoms… read more (such as those that can cause polio-like illnesses) can be cultured, but most other viruses cannot.

The polymerase chain reaction (PCR) technique is used to identify many of the viruses that can cause encephalitis. PCR, which produces many copies of a gene, is used to detect the genetic material of these viruses in a sample of cerebrospinal fluid. Prompt identification of the herpes simplex virus by PCR is difficult, so treatment is usually started immediately if the herpes simplex virus is thought to be the cause. Prompt treatment is essential because the encephalitis it causes is destructive and, if untreated, is often fatal. Immediate treatment can help lessen the severity of symptoms and prevent death.

Rarely, a sample of brain tissue is removed and examined under a microscope (biopsy) to determine whether herpes simplex virus or another organism is the cause.

Sometimes, even after extensive testing, no virus, bacteria, or other cause of infection is identified. In such cases, the cause may be autoimmune or cancer-related (paraneoplastic) encephalitis because tests cannot always confirm those disorders.

• Depending on the possible cause, an antiviral drug, an antibiotic, corticosteroids, and/or other drugs

• Measures to relieve symptoms and, if needed, provide life support

If herpes simplex virus and varicella zoster virus cannot be excluded, the antiviral drug acyclovir is given. Acyclovir is effective against herpes simplex and herpes zoster viruses. Cytomegalovirus encephalitis can be treated with the antiviral drug ganciclovir. Foscarnet is an alternative, which can be used alone or with ganciclovir. Sometimes several antibiotics are also given in case the cause is bacteria.

For HIV-associated encephalopathy, a combination of drugs used to treat HIV infection (antiretroviral drugs Antiretroviral Treatment of Human Immunodeficiency Virus (HIV) Infection Antiretroviral medications used to treat human immunodeficiency virus (HIV) infection aim to do the following: Reduce the amount of HIV RNA (viral load) in the blood to an undetectable amount. .. read more ) helps the immune system function better and delays the progression of the infection and its complications, including dementia.

Autoimmune encephalitis is usually treated with the following:

• Corticosteroids (prednisone or methylprednisolone)

• Plasma exchange Plasma exchange In apheresis, blood is removed from a person and then returned after substances are removed from it. Apheresis can be used to Obtain healthy blood components from a donor to transfuse to a person… read more , which removes the abnormal antibodies from the blood, or immune globulin (antibodies obtained from the blood of people with a normal immune system), which is given intravenously

For other viruses and most other causes, no specific treatment is available. Treatment usually involves relieving symptoms (such as seizures and fever) and, when necessary, providing life support (for example, with a breathing tube) until the infection subsides—in about 1 to 2 weeks.

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Tick-borne encephalitis – causes, symptoms, diagnosis and treatment

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01 February

Tick-borne encephalitis: causes, symptoms, diagnosis and treatment.

Description

Tick-borne encephalitis is a dangerous viral infection that occurs in persistent natural foci, manifested by high fever, intoxication and damage to the nervous system.

Causes of tick-borne encephalitis

The cause of the disease is an RNA-containing tick-borne encephalitis virus, which belongs to the genus of flavoviruses. According to the composition of the genetic material and the place of distribution, the Far Eastern, Ural-Siberian and Western subtypes are distinguished.

The virus is carried by ixodid ticks, which are also its main reservoir.

Thus, the virus occurs where ixodid ticks live, the maximum rise in incidence is observed in May-June, and the second, less pronounced rise is recorded in late summer and early autumn, which is associated with the activity of ticks.

From a person infected with tick-borne encephalitis, the virus is not transmitted to a healthy person.

The tick-borne encephalitis virus enters the human body in the first minutes of a tick bite or, which happens much less often, with the milk of an infected goat, even less often – a cow. Primarily, the virus multiplies and accumulates in the cells of the immune system, then it enters the bloodstream, enters the lymph nodes, liver, spleen and other organs. There it multiplies and attacks the nerve cells of the cervical spinal cord, cerebellum, meninges, remaining there for a long time and penetrating deeper and deeper into the brain tissue.

Classification of the disease

The disease can occur in acute or chronic form.

There are non-focal acute forms , in the clinical picture of which it is not possible to identify a specific damaged structure of the nervous system, and focal acute forms with symptoms indicating the localization of damage to the nervous system.

The severity of tick-borne encephalitis can be mild mild, moderate and severe .

Symptoms of tick-borne encephalitis

The incubation period (from the moment of infection to the first clinical manifestations) averages 7-12 days, but can vary from 1 to 30 days. Rarely during this period there are harbingers of the disease – general malaise, weakness in the muscles of the limbs and neck, numbness of the skin of the face, headache, insomnia, nausea.

The disease begins acutely: with an increase in body temperature to 38-40 ° C, symptoms of intoxication (severe weakness, fatigue, sleep disturbances), as well as symptoms of irritation of the membranes of the brain (nausea, vomiting, severe headache, inability to press the chin to the chest ).

There is lethargy, confusion, redness of the face, neck, upper half of the body. The patient may feel pain in the muscles of the whole body, most of all where movement disorders will subsequently be observed; there may be numbness of the skin or a feeling of crawling, burning, etc.

As the disease develops, the main symptoms appear, which determine its form. Most often, tick-borne encephalitis occurs in the following clinical variants:

• in the form of fever lasting 3-5 days with symptoms of general intoxication, but without signs of damage to the nervous system. The outcome is a quick recovery;
• in the form of damage to the meninges (most common in adults), which is manifested by unbearable headache, dizziness, nausea and vomiting that does not bring relief, photophobia; there is lethargy, lethargy. The body temperature is elevated, the fever lasts 7-14 days. The prognosis is favorable;
• in the form of lesions of the meninges and substance of the brain , when the symptoms of irritation of the meninges are accompanied by movement disorders in the extremities up to paralysis, visual impairment, hearing, speech, difficulty swallowing, etc. Sometimes convulsive seizures occur. The patient is poorly oriented in place and time, delusions and hallucinations are often observed. Recovery takes a long time, often motor disorders remain for life. This is a severe form of tick-borne encephalitis, so a fatal outcome is not excluded;
• in the form of damage to the spinal cord with the development of movement disorders (paresis and paralysis) in the muscles of the neck and limbs;
• in the form of damage to the nerve roots and fibers with the development of sensory disturbances and movements in the limbs.

Separately allocate tick-borne encephalitis with a two-wave course of fever . The first rise in temperature proceeds relatively easily, accompanied by symptoms of intoxication and irritation of the meninges, and the second (after a two-week break) with the deployment of a complete clinical picture with signs of damage to the nervous system. Despite this, the prognosis is favorable, although a transition to the chronic stage is possible.

Tick-borne encephalitis in children often occurs in the form of fever or with signs of damage to the membranes of the brain.

Immunity to the virus after tick-borne encephalitis is lifelong.

Tick-borne encephalitis diagnostics

To diagnose tick-borne encephalitis, it is necessary to confirm the fact of tick bite and the place where it happened (find out if the area is endemic for tick-borne encephalitis), clarify whether the patient was vaccinated and whether he was given immunoglobulin.

The doctor carefully examines the patient and performs a complete neurological examination. It is important to exclude the possibility of other diseases, both infectious and non-infectious nature, accompanied by similar symptoms.

Laboratory diagnosis of tick-borne encephalitis includes determining the presence and increase in the dynamics of the titer of antibodies of the IgM class and antibodies of the IgG class in the blood to the tick-borne encephalitis virus.

IgM anti-tick-borne encephalitis virus

Marker of acute infection with tick-borne encephalitis virus.

TBE virus is an RNA-containing virus of the Flaviviridae family. It belongs to the group of arboviruses, i…

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IgG antibodies to tick-borne encephalitis virus (quantitative)

Marker of current or former tick-borne encephalitis virus infection.

TBE virus is an RNA-containing virus of the Flaviviridae family. It belongs to the Arbovi. ..

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In a hospital, the composition of the cerebrospinal fluid (CSF) is studied, and the presence of genetic material (RNA) of the tick-borne encephalitis virus in the blood and cerebrospinal fluid is also detected.

To determine the degree of damage to the structures of the nervous system, electroencephalography, computed tomography of the brain or magnetic resonance imaging of the brain is recommended.

Electroencephalography (EEG)

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CT scan of the brain and skull

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MRI of the brain

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Which doctors to contact

If a tick is found on the body, it is best to contact the nearest trauma center, where it will be removed and the issue of emergency prevention of tick-borne encephalitis will be decided.

If seeking medical help for some reason is not possible, then the tick must be removed on its own, placed in an airtight jar with a small piece of cotton soaked in water, and taken to the laboratory to be tested for tick-borne encephalitis and other infections.

Laboratory testing of ticks to detect RNA/DNA pathogens transmitted by ixodid ticks: tick-borne encephalitis, borreliosis (Lyme disease)

Synonyms: ixodid tick; tick-borne encephalitis, tick-borne encephalitis virus; systemic tick-borne borreliosis (Lyme disease), tick-borne meningopolyneuritis, tick-borne borre. ..

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If, according to the results of laboratory analysis, the tick turned out to be a carrier of the tick-borne encephalitis virus, it is necessary to consult with a specialist (infectionist) to determine the further algorithm of actions.

At the first clinical manifestations, you should immediately seek medical help from a general practitioner, therapist or call an ambulance, be sure to report the fact of a tick bite. A patient with tick-borne encephalitis does not pose a danger to others. Treatment is carried out in the conditions of an infectious diseases hospital jointly by infectious disease doctors, neurologists and other specialists.

Treatment of tick-borne encephalitis

Treatment of tick-borne encephalitis should be started as early as possible. For these purposes, anti-tick immunoglobulin, antiviral drugs that act on the RNA of the virus, interferon preparations, and interferon inducers are used.

Carry out therapy that reduces intoxication, improves cerebral circulation, reduces pain. According to indications, anticonvulsant, antioxidant drugs are used.

Complications

The following complications of tick-borne encephalitis in the acute period of the disease with damage to the brain substance are possible: cerebral edema with subsequent respiratory failure, cardiac activity and coma, hemorrhages in the brain tissue.

When a bacterial infection is attached, inflammation of the ENT organs, lungs, kidneys and other body systems develops.

Residual phenomena in the form of paresis and paralysis, muscle atrophy (a decrease in their mass) lead to disability. Possible cosmetic defects – strabismus, facial asymmetry, etc.

Disease prevention

There is a planned specific prevention of tick-borne encephalitis – vaccination.

Vaccination with the drug “Tick-E-Vac” for the prevention of tick-borne encephalitis (children – from one to 16 years old)

Vaccination to develop immunity against tick-borne encephalitis, a dangerous infection that can cause damage to the brain and spinal cord…

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According to the main scheme, it is carried out twice with a break of at least a month and subsequent revaccinations in a year, and then every 3 years. The emergency regimen involves the introduction of two doses of the vaccine with a two-week interval, the third is administered a year later.

After two main vaccinations, immunity is developed within two weeks, which should be considered when planning trips to dangerous areas.

If a tick has been sucked, and the patient has not been vaccinated or has completed an incomplete vaccination course and there is a high risk of infection (provided that the tick is infected or there were several bites), then emergency specific prophylaxis is carried out – no later than 96 hours after the tick is sucked, immunoglobulin is administered (ready-made antibodies against tick-borne encephalitis).

Not earlier than 10 days after the bite of an infected tick, it is recommended to test for the detection of antibodies to the tick-borne encephalitis virus in the blood. Antibodies of the IgM class appear first and are indicators of an incipient infection, then antibodies of the IgG class are produced fairly quickly.

IgM antibodies to tick-borne encephalitis virus

Marker of acute infection with tick-borne encephalitis virus.

TBE virus is an RNA-containing virus of the Flaviviridae family. It belongs to the group of arboviruses, i…

Up to 5 business days

Available with home visit

830 RUB

Add to cart

IgG antibodies to tick-borne encephalitis virus (quantitative)

Marker of current or former tick-borne encephalitis virus infection.

TBE virus is an RNA-containing virus of the Flaviviridae family. It belongs to the Arbovi…

Up to 5 business days

Available with home visit

830 RUB

Add to cart

The general rules of prevention are to minimize the risk of tick bite: during the period of maximum activity of ticks, one should not walk on high forest and park grass, through bushes.

Ticks do not like high temperatures, bright sun and moisture, so on hot clear days they attack in the morning (when the dew dries) and in the evening, on cloudy days – throughout the day. At air temperatures below 10℃, the activity of mites decreases.

Clothing should cover the whole body, sleeves should fit snugly, it is better to tuck trousers into socks, a hat is required. It is necessary to use special anti-tick repellents (apply according to the instructions, more often they are applied to clothing).

Upon returning from the forest and park areas, you need to fully examine yourself, ticks like to stick in those areas where the skin is the thinnest – on the neck, in the armpits, popliteal fossae. As a rule, the tick does not stick immediately after it hits the body, but looks for a convenient place where the skin is thin, so there is time to notice the crawling tick and get rid of it. It is better to shake out the clothes and then wash them in hot water, since the larval forms of mites are light and difficult to notice.

If the tick has stuck, and there is no way to seek qualified help, you should remove the tick with tweezers or thread with rocking and twisting movements (it is better to do this with gloves), and then treat the wound with a disinfectant.

You should not put pressure on the body of the tick, you can not use oil, gasoline, kerosene, cauterize the tick, all this increases the risk of infection.

Sources:

1. Gayvoronsky A. G., Galitskaya M.G., Namazova-Baranova L.S. Etiology, clinical manifestations, treatment and prevention of tick-borne encephalitis // Pediatric Pharmacology, 2013. V. 10. No. 2. P. 34–39.
2. Clinical practice guideline: TBE in adults / International Association of Infection Professionals, 2016.

IMPORTANT!

The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.
For a correct assessment of the results of your analyzes in dynamics, it is preferable to do studies in the same laboratory, since different laboratories may use different research methods and units of measurement to perform the same analyzes.

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what you need to know about the disease carried by ticks

Content

• 1 Ticks in the taiga: what disease can they transmit?
  • 1.1 Tick-borne encephalitis in the taiga: key facts
  • 1.2 Tick-borne encephalitis: what is this disease?
    • 1.2.1 What are mites and how can they cause TBE?
    • 1.2.2 What happens when a disease develops?
    • 1. 2.3 How to protect yourself from CE?
  • 1.3 How is tick-borne encephalitis transmitted?
  • 1.4 Symptoms of the disease: what you should know about the clinic of tick-borne encephalitis in the taiga
    • 1.4.1 Early stage of the disease
    • 1.4.2 Progression stage
    • 1.4.3 Advanced stage
    • 1.4.4 Conclusion
  • 1.5 Diagnosis and treatment of tick-borne encephalitis
    • 1.5.1 Diagnosis
    • 1.5.2 Treatment
  • 1.6 How to prevent TBE infection?
    • 1.6.1 Clothing and footwear
    • 1.6.2 Use repellents and insecticides
    • 1.6.3 Check insects
  • 1.7 Regions of Russia where tick-borne encephalitis occurs
    90 009 1.7.1 List of regions of Russia, where cases of tick-borne encephalitis are common:
  • 1.8 Tick-borne encephalitis in the taiga
    • 1.8.1 Features of TBE distribution in the taiga
  • 1.9 Dangers in the taiga for vacationers and residents: how not to become a victim of tick-borne encephalitis?
    • 1. 9.1 Ticks are a dangerous enemy for everyone who spends time in the forest and in nature
    • 1.9.2 Local residents are also at risk
  • 1.10 Prevention and control of ticks
  • 1.11 Main directions of medical research by EC
    • 1.11.1 Strategies for disease prevention and control
    • 1.11.2 Diagnosis and treatment
    • 1.11.3 Investigation of the TBE virus and its epidemiology
  • 1.12 Related videos:
  • 1.13 Q&A:
    • 9 0068
    • 1.13.0.1 What is tick-borne encephalitis?
    • 1.13.0.2 How is tick-borne encephalitis spread?
    • 1.13.0.3 What should I do to protect myself from ticks that carry encephalitis?
    • 1.13.0.4 What are the symptoms of tick-borne encephalitis?
    • 1.13.0.5 What is the probable prognosis for recovery from tick-borne encephalitis?
    • 1.13.0.6 Are all regions of Russia at risk for tick-borne encephalitis infection?

Find out the name of a dangerous disease that ticks can carry in the taiga. Be prepared to travel and protect your health from tick-borne infections.

Tick-borne encephalitis (TBE) is a serious infectious disease of the central nervous system carried by certain types of ticks. The risk of TBE infection is especially high in the taiga – the taigas of Russia.

There are two types of CE – European and Far Eastern, each of which has its own characteristics. The European type is found in Scandinavia, Central and Eastern Europe, and the Far Eastern type is found in China, Japan and Russia. Despite the differences between the types, the symptoms of the disease are the same: headache, fever, convulsions and weakening of muscle tone.

There is a vaccine for TBE, but it is not 100% effective, so the most effective way to protect against the disease is to prevent tick bites. Clothing that protects the body, sprays and anti-mite creams are effective ways to protect yourself. If you go massively into forests or other places where you feel an increased likelihood of encountering ticks, physical barriers are needed to protect against bites.

Tick-borne encephalitis in the taiga: basic facts

Tick-borne encephalitis is a disease that is transmitted to humans through the bite of an infected tick. The main symptoms of the disease are high fever, headache, vomiting, convulsions and even paralysis.

The taiga is one of the main natural habitats for ticks that can carry this dangerous disease. The risk of contracting tick-borne encephalitis increases in people whose lifestyle is connected with nature, such as hunters, fishermen, tourists and lumberjacks.

• Prevention is the best protection: Wearing protective clothing, using repellents, and avoiding tick-infested areas reduce the risk of contracting tick-borne encephalitis.
• Vaccination: A tick-borne encephalitis vaccine is available to reduce the risk of infection. These vaccinations are recommended for everyone who is constantly in nature.
• Treatment: There is currently no specific treatment for tick-borne encephalitis, so the focus is on symptomatic therapy and measures to reduce inflammation and combat life-threatening symptoms.

Tick-borne encephalitis: what is this disease?

What are mites and how can they cause TBE?

Ticks are small insects that carry various infections. TBE is caused by a virus that is transmitted to humans through the bite of an infected tick. However, not all ticks can be called TBE carriers.

Ticks that live in the taiga are often carriers of TBE. Symptoms of the disease may appear a few days after the bite.

What happens during the development of the disease?

EC attacks the central nervous system, causing inflammation of the brain and spinal cord. Symptoms of the disease are high body temperature, headache, nausea, vomiting, convulsions, limited movement and decreased perception of everything around.

Complications from EC can be serious and even fatal.

How to protect yourself from CE?

1. Wear protective clothing when visiting the taiga.
2. Use insect repellent to keep ticks away.
3. Check your body and clothes for ticks after a walk in nature.
4. Take out insurance before traveling to the taiga so that it covers the cost of treatment if necessary.

Although TE can be a serious and dangerous disease, it can be prevented by following a few simple precautions.

How is tick-borne encephalitis transmitted?

Tick-borne encephalitis is an acute viral infection transmitted by the bite of an infected tick. The main carrier of the virus is the forest tick, which can become infected with the virus when it bites an infected animal.

After being bitten by an infected tick, the virus enters the human bloodstream. Initially, it spreads through the circulatory system and then begins to affect the nervous system.

The risk of infection is especially high in the taiga, where there are a large number of infected ticks. Therefore, it is important to take precautions, including the use of special repellents and clothing that covers the body. After a walk in the forest or in nature, it is necessary to carefully examine the body for the presence of ticks and remove them if found.

Symptoms of the disease: what you should know about the clinic of tick-borne encephalitis in the taiga

Early stage of the disease

Symptoms of the clinic of tick-borne encephalitis first appear as general health problems. Usually, at the first stage, the disease is accompanied by weakness, headache and vomiting. An increase in body temperature is also possible.

Progression stage

After the first symptoms begin to respond, within 2-7 days further, the second stage of the disease may begin. At this stage, patients already experience headaches, nausea, vomiting, dizziness, as well as pain in the muscles of all parts of the body. Often there are problems with sleep and there is a general feeling of fatigue.

Advanced

After 2-3 days of more moderate symptoms, an advanced stage is possible. In this case, the development of an acute infection of the brain is possible, which is manifested by severe headaches, muscle paralysis and a change – sometimes to the point of complete loss – of consciousness. In case of untimely seeking medical help, one of the last stages of the disease occurs, where complex therapy and cardinal treatment are necessary.

Conclusion

If signs and symptoms of tick-borne encephalitis appear, you should immediately seek qualified medical attention, as this disease can lead to even more serious consequences.

Diagnosis and treatment of tick-borne encephalitis

Diagnosis

TBE is a serious disease that can cause injury and disability. Early diagnosis of the disease is extremely important, so you need to pay attention to the following symptoms:

• headache;
• disturbance of sleep and appetite;
• convulsive movements;
• impaired coordination and vision;
• high body temperature.

Diagnosis of the disease is carried out on the basis of blood tests and cerebrospinal fluid. There are specific laboratory diagnostic methods that allow you to determine the presence of antibodies to the tick-borne encephalitis virus.

Treatment

As a rule, the treatment of tick-borne encephalitis is symptomatic and supportive therapy. At the initial stage of the disease, immunotherapy is indicated in the form of the introduction of immunoglobulins. In severe cases, antiviral drugs may be used.

Although tick-borne encephalitis is a very dangerous disease, it can be prevented by taking preventive measures. It is important to use tick protection when you are outdoors, check your body regularly for ticks, and practice good hygiene.

How to prevent TBE infection?

Protection against ticks and the diseases they transmit is important for those who travel to the taiga for recreation or work. A few simple steps can significantly reduce the risk of contracting tick-borne encephalitis.

Clothing and footwear

Dress in layers to avoid tick bites in open areas. It is especially important not to forget about boots or high boots that protect your feet from ticks. Clothing should cover most of the body and be light in color so insects can be seen.

Use repellents and ticks

Repellents should be used if you plan to spend time in nature. They contain substances that ticks do not like and make them keep their distance from the body. There are also special anti-tick products for clothing and equipment that effectively repel insects.

Don’t forget to check for insects

After a walk in nature, you should check yourself and your loved ones for the presence of mites, which may be on clothing or skin. The most important thing is to remove them as quickly as possible. Remember that the tick-borne encephalitis virus can be transmitted within hours of being bitten by a tick.

Compliance with these simple rules will help to avoid infection with tick-borne encephalitis in the taiga.

Regions of Russia where tick-borne encephalitis occurs

Tick-borne encephalitis is a dangerous infectious disease transmitted to humans through the bite of a tick. Russia is one of the countries with the highest number of cases.

The most dangerous is the European tick, which lives in various regions of the country. There are also several regions that are considered endemic for tick-borne encephalitis.

List of Russian regions where cases of tick-borne encephalitis are common:

• Vologda region.
• Sverdlovsk region.
• Perm region.
• Moscow region.
• Krasnoyarsk Territory.
• Karelia.

You should also be careful when traveling to the steppe and forest areas, as the risk of infection increases in their territories. Do not forget about precautions when visiting areas where ticks can live.

To prevent tick-borne encephalitis, use insect repellent, wear light-colored and thick clothing with protection against ticks, and, if necessary, see a doctor for vaccination.

Tick-borne encephalitis in the taiga

TBE distribution in the taiga

Tick-borne encephalitis (TBE) is a dangerous disease carried by ticks. It is widespread in the taiga, where there are a large number of ticks, carriers of the pathogen.

In the taiga, people who are engaged in hunting, fishing, tourism, as well as lumberjacks most often fall ill. Such people often enter areas where the saturation of ticks is high and have an increased risk of TBE infection.

To protect against tick-borne encephalitis in the taiga, precautions must be taken, including the wearing of protective clothing and the treatment of clothing and skin with repellents, and, of course, vaccination.

In general, to prevent the spread of TBE in the taiga, it is necessary to carry out information work about the disease, the risks of infection and precautions to prevent the disease. This will help reduce the number of cases of the disease and reduce the number of carriers of the pathogen in natural conditions.

Dangers in the taiga for vacationers and residents: how not to become a victim of tick-borne encephalitis?

Ticks are a dangerous enemy for everyone who spends time in the forest and in nature

For those who enjoy outdoor activities, being aware of the possible danger posed by ticks is important. Taiga is a favorite place for walks and picnics, but lack of caution can cause infection with tick-borne encephalitis, a dangerous infectious disease. It should be remembered that the tick-borne encephalitis virus is present in the saliva of ticks and can be transmitted to humans.

What measures should be taken to avoid becoming a victim of a dangerous disease? First of all, it is important to observe safety measures and use protective equipment – repellents, long-sleeved clothing and pants. Examine your skin regularly to remove already attached mites. If you notice a tick on your body, do not try to remove it yourself – consult a doctor.

Local residents are also at risk

Not only tourists and campers are at risk of contracting tick-borne encephalitis. There is also danger for the local residents of the taiga, who are engaged in logging and hunting. The risk of infection is especially high among people whose work is associated with a regular stay in the forest.

Therefore, everyone should know not only about the symptoms and treatment of the disease, but also about the possibility of preventing it. Be careful and take the necessary precautions to make your outdoor trips safe and enjoyable.

Prevention and control of ticks

There are a few simple rules to follow to prevent a tick bite. First, it is necessary to use insect repellents containing active substances that repel ticks. Secondly, when visiting forests or parks, wear light-colored, thick clothing that can protect the body from infection. It is also desirable to close the collar and cuffs.

Seek medical attention if symptoms suggest infection. In case of timely treatment to the doctor, serious consequences can be avoided.

• Use insect repellent.
• Wear light, heavy clothing.
• Examine the body for ticks.
• Seek medical attention if symptoms occur.

TBE Medical Research Focus

Disease Prevention and Control Strategies

Scientists and medical experts spend a lot of time studying TBE prevention and control strategies. The most effective methods are vaccination and control of the tick population. Researchers are also exploring potential new methods to combat the disease, such as the use of repellents and new tissue processing technologies.

Diagnosis and treatment

One of the key areas of research is to improve the diagnosis and treatment of TBE. Existing diagnostic methods include analysis of blood and cerebrospinal fluid for the presence of antibodies to the virus, but their accuracy is not always high. Research can help improve these methods, leading to more accurate diagnosis and more effective treatment.

Investigation of the TBE virus and its epidemiology

The study of the TBE virus itself is another important area of ​​research. Although the virus was discovered many years ago, not all of its biology is still widely known. Research can also help identify factors that influence the spread of the disease, such as climate change, insect host behavior, vitamin D deficiency, and others.

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Q&A:

What is tick-borne encephalitis?

Tick-borne encephalitis is a viral disease of the central nervous system transmitted by ticks. It can lead to inflammation of the brain and spinal cord and can cause serious complications.

How is tick-borne encephalitis spread?

Tick-borne encephalitis is transmitted by tick bites. Ticks infected with the virus live in taiga forests and meadows. People can become infected when they visit these places during the tick season (spring-summer).

What can you do to protect yourself from ticks that carry encephalitis?

Protective clothing impregnated with repellents (insect repellents) must be worn before hiking in the forest. While walking, you should avoid high grass and swampy places where ticks live.