Encephalitis is inflammation of the brain that is usually caused by a viral infection. Symptoms can range from mild flu-like symptoms to more severe effects like confusion, seizures, or paralysis. While often mild, encephalitis can sometimes be life-threatening. Diagnosis involves brain imaging, spinal taps, and testing of bodily fluids. Treatment depends on the cause but may include antiviral medications, supportive care, and physical/occupational therapy for complications.

1. SUBJECT – MEDICAL SURGICAL NURSING – II
CLASS – BSC NURSING 3RD YEAR
TOPIC – ENCEPHALITIS
INTRODUCTION
Encephalitis is inflammation of the brain. There are several causes,
but the most common is a viral infection.
Encephalitis often causes only mild flu-like signs and symptoms —
such as a fever or headache — or no symptoms at all. Sometimes
the flu-like symptoms are more severe. Encephalitis can also cause
confused thinking, seizures, or problems with movement or with
senses such as sight or hearing.
In some cases, encephalitis can be life-threatening. Timely
diagnosis and treatment are important because it's difficult to predict
how encephalitis will affect each individual.
SYMPTOMS
Most people with viral encephalitis have mild flu-like symptoms,
such as:
 Headache
 Fever
 Aches in muscles or joints
 Fatigue or weakness
Sometimes the signs and symptoms are more severe, and might
include:
 Confusion, agitation or hallucinations
 Seizures

2.  Loss of sensation or paralysis in certain areas of the face or
body
 Muscle weakness
 Problems with speech or hearing
 Loss of consciousness (including coma)
In infants and young children, signs and symptoms might also
include:
 Bulging in the soft spots (fontanels) of an infant's skull
 Nausea and vomiting
 Body stiffness
 Poor feeding or not waking for a feeding
 Irritability

3. BULGING FONTANEL
One of the major signs of encephalitis in infants is bulging of the soft
spots (fontanels) of the baby's skull. Pictured here is the anterior
fontanel. Other fontanels are found on the sides and back of an
infant's head.
CAUSES
The exact cause of encephalitis is often unknown. But when a
cause is known, the most common is a viral infection. Bacterial
infections and noninfectious inflammatory conditions also can cause
encephalitis.
There are two main types of encephalitis:
 Primary encephalitis. This condition occurs when a virus or
other agent directly infects the brain. The infection may be
concentrated in one area or widespread. A primary infection
may be a reactivation of a virus that had been inactive after a
previous illness.
 Secondary encephalitis. This condition results from a faulty
immune system reaction to an infection elsewhere in the body.
Instead of attacking only the cells causing the infection, the
immune system also mistakenly attacks healthy cells in the
brain. Also known as post-infection encephalitis, secondary
encephalitis often occurs two to three weeks after the initial
infection.
COMMONVIRAL CAUSES
The viruses that can cause encephalitis include:
 Herpes simplex virus (HSV). Both HSV type 1 — associated
with cold sores and fever blisters around your mouth —
and HSV type 2 — associated with genital herpes — can cause
encephalitis. Encephalitis caused by HSV type 1 is rare but can
result in significant brain damage or death.

4.  Other herpes viruses. These include the Epstein-Barr virus,
which commonly causes infectious mononucleosis, and the
varicella-zoster virus, which commonly causes chickenpox and
shingles.
 Enteroviruses. These viruses include the poliovirus and the
coxsackievirus, which usually cause an illness with flu-like
symptoms, eye inflammation and abdominal pain.
 Mosquito-borne viruses. These viruses can cause infections
such as West Nile, La Crosse, St. Louis, western equine and
eastern equine encephalitis. Symptoms of an infection might
appear within a few days to a couple of weeks after exposure to
a mosquito-borne virus.
West Nile virus transmission cycle
 Tick-borne viruses. The Powassan virus is carried by ticks and
causes encephalitis in the Midwestern United States.
Symptoms usually appear about a week after a bite from an
infected tick.
 Rabies virus. Infection with the rabies virus, which is usually
transmitted by a bite from an infected animal, causes a rapid

5. progression to encephalitis once symptoms begin. Rabies is a
rare cause of encephalitis in the United States.
 Childhood infections. Common childhood infections — such
as measles (rubella), mumps and German measles (rubella) —
used to be fairly common causes of secondary encephalitis.
These causes are now rare in the United States due to the
availability of vaccinations for these diseases.
RISK FACTORS
Anyone can develop encephalitis. Factors that may increase the risk
include:
 Age. Some types of encephalitis are more common or more
severe in certain age groups. In general, young children and
older adults are at greater risk of most types of viral
encephalitis.
 Weakenedimmune system. People who have HIV/AIDS, take
immune-suppressing drugs or have another condition causing a
weakened immune system are at increased risk of encephalitis.
 Geographical regions. Mosquito- or tick-borne viruses are
common in particular geographical regions.
 Season of the year. Mosquito- and tick-borne diseases tend to
be more common in summer in many areas of the United
States.
COMPLICATIONS
The complications of encephalitis vary, depending on factors such
as:
 Your age
 The cause of your infection
 The severity of your initial illness
 The time from disease onset to treatment

6. People with relatively mild illness usually recover within a few weeks
with no long-term complications.
COMPLICATIONS OF SEVERE ILLNESS
Inflammation can injure the brain, possibly resulting in a coma or
death.
Other complications — varying greatly in severity — may persist for
months or be permanent. These complications can include:
 Persistent fatigue
 Weakness or lack of muscle coordination
 Personality changes
 Memory problems
 Paralysis
 Hearing or vision defects
 Speech impairments
PREVENTION
The best way to prevent viral encephalitis is to take precautions to
avoid exposure to viruses that can cause the disease. Try to:
 Practice good hygiene. Wash hands frequently and thoroughly
with soap and water, particularly after using the toilet and before
and after meals.
 Don't share utensils. Don't share tableware and beverages.
 Teach your children good habits. Make sure they practice
good hygiene and avoid sharing utensils at home and school.
 Get vaccinations. Keep you’re own and your children's
vaccinations current. Before traveling, talk to your doctor about
recommended vaccinations for different destinations.

7. PROTECTIONAGAINST MOSQUITOES AND TICKS
To minimize your exposure to mosquitoes and ticks:
 Dress to protect yourself. Wear long-sleeved shirts and long
pants if you're outside between dusk and dawn when
mosquitoes are most active, and when you're in a wooded area
with tall grasses and shrubs where ticks are more common.
 Apply mosquito repellent. Chemicals such as DEET can be
applied to both the skin and clothes. To apply repellent to your
face, spray it on your hands and then wipe it on your face. If
you're using both sunscreen and a repellent, apply sunscreen
first.
 Use insecticide. The Environmental Protection Agency
recommends the use of products containing permethrin, which
repels and kills ticks and mosquitoes. These products can be
sprayed on clothing, tents and other outdoor gear. Permethrin
shouldn't be applied to the skin.
 Avoid mosquitoes. Refrain from unnecessary activity in places
where mosquitoes are most common. If possible, avoid being
outdoors from dusk till dawn, when mosquitoes are most active.
Repair broken windows and screens.
 Get rid of water sources outside your home. Eliminate
standing water in your yard, where mosquitoes can lay their
eggs. Common problems include flowerpots or other gardening
containers, flat roofs, old tires and clogged gutters.
 Look for outdoor signs of viral disease. If you notice sick or
dying birds or animals, report your observations to your local
health department.
PROTECTIONFOR YOUNG CHILDREN
Insect repellents aren't recommended for use on infants younger
than 2 months of age. Instead, cover an infant carrier or stroller with
mosquito netting.

8. DIAGNOSIS
Your doctor will start with a thorough physical examination and
medical history.
Your doctor might then recommend:
 Brain imaging. MRI or CT images can reveal any swelling of
the brain or another condition that might be causing your
symptoms, such as a tumor.
 Spinal tap (lumbar puncture). A needle inserted into your
lower back removes a small amount of cerebrospinal fluid
(CSF), the protective fluid that surrounds the brain and spinal
column. Changes in this fluid can indicate infection and
inflammation in the brain. Sometimes samples of CSF can be
tested to identify the virus or other infectious agent.
 Other lab tests. Samples of blood, urine or excretions from the
back of the throat can be tested for viruses or other infectious
agents.
 Electroencephalogram (EEG). Electrodes affixed to your scalp
record the brain's electrical activity. Certain abnormal patterns
may indicate a diagnosis of encephalitis.
 Brain biopsy. Rarely, a small sample of brain tissue might be
removed for testing. A brain biopsy is usually done only if
symptoms are worsening and treatments are having no effect
TREATMENT
Treatment for mild encephalitis usually consists of:
 Bed rest
 Plenty of fluids
 Anti-inflammatory drugs — such as acetaminophen (Tylenol,
others), ibuprofen (Advil, Motrin IB, others) and naproxen
sodium (Aleve) — to relieve headaches and fevers

9. Antiviral drugs
Encephalitis caused by certain viruses usually requires antiviral
treatment.
Antiviral medications commonly used to treat encephalitis include:
 Acyclovir (Zovirax)
 Ganciclovir (Cytovene)
 Foscarnet (Foscavir)
Some viruses, such as insect-borne viruses, don't respond to these
treatments. But because the specific virus may not be identified
immediately or at all, doctors often recommend immediate treatment
with acyclovir. Acyclovir can be effective against HSV, which can
result in significant complications when not treated promptly.
Antiviral medications are generally well tolerated. Rarely, side
effects can include kidney damage.
SUPPORTIVE CARE
People who are hospitalized with severe encephalitis might need:
 Breathing assistance, as well as careful monitoring of breathing
and heart function
 Intravenous fluids to ensure proper hydration and levels of
essential minerals
 Anti-inflammatory drugs, such as corticosteroids, to reduce
swelling and pressure within the skull
 Anticonvulsant medications, such as phenytoin (Dilantin), to
stop or prevent seizures
If you experience complications of encephalitis, you might need
additional therapy, such as:

10.  Physical therapy to improve strength, flexibility, balance, motor
coordination and mobility
 Occupational therapy to develop everyday skills and to use
adaptive products that help with everyday activities
 Speech therapy to relearn muscle control and coordination to
produce speech
 Psychotherapy to learn coping strategies and new behavioral
skills to improve mood disorders or address personality
changes