Japanese encephalitis

2. JAPANESE ENCEPHALITIS
Japanese encephalitis is a
mosquito-borne viral infection.
Japanese Encephalitis is the
inflammation of brain,due to Group B
Arbo virus transmitted by Culex
mosquitoes.
It is directly affect to the central
nervous system and may cause severe
complications.

3. Incidence
Japanese encephalitis is most common in Japan,
widespread throughout SoutheastAsia.
China, Korea, Japan, Taiwan, and Thailand have
had outbreaks in the past, but they have mainly
controlled the disease byvaccination.
In India,It was diagnosed first time in 1995 at
Vellore, and in Assam, UP,Bihar,TNhas been
reported later.
The majority of cases about 85% among children
below 15 years of age.

4. Epidemiological Triad
Agent
Host Environment

5. Agent
Group B Arbo virus in the genius group of
Flaviviridae
Domestic pigs and wild birds
(especially herons) are reservoirs of the
virus.

6. Host
All age groups & Both gender
More in children under 15 years of
age
Environment
Rainy season.

7. Incubation Period
 5-15 days.
Clinical Manifestations
Clinical features are divided into 3
stages:
1. Prodromal stage
2. Acute Encephalitic stage
3. Late stage

8. 1. Prodromal stage
The onset of illness is usually acute & the
duration of this stage is usually 1-6 days.
Fever(38-41’c)
Headache
 Rigors (Intensive shivering)
GI disturbances
Nausea & Vomiting
Lethargy

9. 2. Acute Encephalitic stage
 This stage begins by 3-5th day
 High grade fever
 Nuchal rigidity
 Convulsions signs of increased ICP
 Unconsciousness
 Dystonia
 Dysphasia
 Hemiplegia
 Quadriplegia

10. 3. Late stage
This stage begins when active
inflammation reduced
ie,the temperature & ESR touch
normal.
CNS involvement is more in this stage.
Mental impairment
Epilepsy
Behavioural abnormalities.
The average period between the onset of
illness and death is about 9 days only.

11. Laboratory Diagnosis
• Detection of Antigen from serum or
cerebrospinal fluid (CSF) to detect virus-
specific IgM antibodies within 7 days of
onset of disease.
• Compliment Fixation Test: Todetect the
antibodies for infection.
• Neutralization Test: Todetect the
presence of virus infections.
• Immunofluorescence Assay: Todetect the
antigen & antibodies

12. Laboratory Diagnosis
Confirmatory testing is only available
at CDC (Centers for Disease Control and
Prevention) and a few specialized
reference laboratories.
Healthcare providers should contact
their state or local health department
or the CDC Arboviral Diseases Branch
for assistance with diagnostic testing

13. Prevention & Control of Japanese Encephalitis
1. Early Detection,First Aid & Referral
 JE can be recognised by following
symptoms and first Aid can be given by
parents till the child is shifted to the
hospital;
 Fever
Loss of consciousness or altered
behavioural changes over 1 hour to 4 days
Observe for new development of
symptoms like abnormal movements &
posture,Squint,mouth deviating to one
side.

14. Guidelines for parents
While shifting the child to hospital,:
Keep the nose & mouth clean and
saliva should be cleared from
mouth.
Keep the child on one side with
head in a little lower position
If cold,wrap in a cloth & if fever,do
sponging.

15. 2. Vaccination
Japanese encephalitis vaccine

17. 3. Vector control
• Chemical Control
Insecticides.eg: malathion, fenitrothion
• Biological Control
Larvivorous fish are those that feed on
immature stages of mosquitoes where the
stagnation of water for their growth.
• Personal Prophylactic Measures
Bed mosquito nets, wear long sleeves to
cover the exposure body parts,mosquito
repellents.

18. Medical Management of Japanese
Encephalitis
Control Hyperthermia by
hydrotherapy & antipyretics.
eg:Paracetamol
Manage convulsion with anti-convulsive
drugs such as:
Phenytoin 15-20mg/kg
Diazepam 0.1-0.3 mg/kg (sedative)

19. Maintain ICP with initial dose of
Mannitol 2.5 ml/kg of 20% solution to
be given.
After 30 minutes of mannitol
infusion,re-assess the ICP and still
increased,then administer Frusemide
1mg/kg in Q12H
Symptomatic treatment

20. Nursing Management
•Assess the condition of the
patient
• Monitor vital signs
• Maintain Intake-output chart.
• Monitor BP & potassium level frequently.
• Maintain fluid & electrolyte balance to
prevent Hypovolemia.
• Provide thorough mouth care.

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