Download Japanese Encephalitis

Rahul Kapoor
Japanese Encephalitis
 Affects CNS and can cause severe complications and
even death.
 Cause : Japanese Encephalitis virus (arbovirus)
 Vector : Rice field breeding mosquito primarily Culex
tritaeniorhynchus
 No human to human transmission.
 It is most seen in Southeast Asia and the Far East.
 30,000-50,000 cases are reported annually.
Basic Transmission Cycle
 Mosquitos become
infected by feeding on
pigs and wild birds
infected with JEV.
 The JE virus is amplified
in the blood of pigs and
wild birds.
 The infected mosquitos
transfer the amplified
virus to humans and
animals.
Pathophysiology
• The virus initially propagates
at the site of the bite and the
regional lymph nodes.
• Viremia develops causing
inflammatory changes in
heart, liver, lungs and
reticuloendothelial system.
• Neurologic invasion can
develop, possibly by growth of
the virus across vascular
endothelial cells.
•Large areas of brain can be
involved including basal
ganglia, thalamus, brains
stem, hippocampus and
cerebral cortex
Signs and Symptoms
 Symptoms usually appear after 6-8 days after the mosquito
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bite.
MILD INFECTION : No apparent symptoms except fever +
headache
SEVERE INFECTION: Quick onset of high fever,
headache, neck stiffness, disorientation, tremors, coma,
occasional convulsions and spastic paralysis.
If it progresses to encephalitis, it can be fatal in 30% of the
cases.
Among the survivors, 30% have serious brain damage,
including paralysis.
Diagnosis is based on tests of blood or CSF.
Occurrence around the Globe
 JE is the leading cause of viral
encephalitis in Asia.
 30,000-50,000 cases each year.
 Countries which have had major
epidemics in the past, but which
have controlled the disease
primarily by vaccination, include
China, Korea, Japan, Taiwan and
Thailand.
 Countries that still have periodic
epidemics include Vietnam,
Cambodia, Myanmar, India, Nepal,
and Malaysia.
Japanese Encephalitis is seen in southeast Asia and far
east
Treatment and Prevention
 No anti viral drugs have been
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discovered against JE so far.
Intensive Supportive Therapy
(nutrition, control of infection,
intensive care) is indicated.
Vaccines against JEV provide
immunity against the virus.
Can also be prevented by
preventing mosquito bite (use of
repellents etc)
Drainage of stagnant water.
Acknowledgement
 www.google.co.in
 http://gkpdiv.up.nic.in
 www.cdc.gov/ncidod/dvbid/jencephalitis/qa.htm
 www.sumerdoc.blogspot.com
 www.arbovirus.health.nsw.gov.au
fin
Thanks for your
attention 