1. JAPANESE ENCEPHALITIS
VIROLOGY PRESENTATION

2. GROUP MEMBERS:
SYEDA KANWAL FATIMA
NIMRAH GHOURI

3. CONTENTS Introduction Epidemiology Causes Symptoms
Life cycle and replication
Transmission
Diagnosis
Treatment and prevention
References
cycle

4. INTRODUCTION viral disease Infects animals and humans
A mosquito-borne flavivirus
JE is mainly a problem in rural farming areas.
Occurs more commonly in the rainy season.
Affect the CNS and cause severe complications and death.

5. TAXONOMY Group: Group IV ((+)ssRNA) Family: Flaviviridae
Genus: Flavivirus
Species: Japanese encephalitis virus

6. EPIDEMIOLOGY
JE is endemic throughout most of Asia and parts of the Western Pacific region.
Within the JE-endemic region, there are two typical patterns of transmission:
In areas with temperate climates, most cases occur over a period of several months when the weather is warmest, usually after the monsoons begin or associated with heavy rainfall.
In areas with tropical climates, there is year-round transmission.

7. Distribution of Japanese encephalitis in Asia

8. Different patterns of age distribution of cases

9. Death and disability from JE
Up to 30% of all patients with JE die.
For those that survive the illness, 30% to 75% cases are left with disability.
Disability is both physical and cognitive.
Photo credit: Julie Jacobson

10. EVOLUTION
originated from its ancestral virus in the mid 1500s in the Indonesia-Malaysia region
evolved there into different genotypes and spread across Asia.

11. CAUSES AND SYMPTOMS caused by an arbovirus (arthropod-borne virus)
Arboviruses are a large group of viruses that are spread by certain invertebrate animals (arthropods)
most commonly, blood-sucking insects.
Like most arboviruses, JE is spread by infected mosquitoes..

12. SYMPTOMS AFTER TWO DAYS: Suffer the effects of swelling in the brain
Prob. With balancing and coordination
Tremors
Paralysis
Seizure
Lapses in consciousness
Mask like appearance of the face
if the patient survives the illness, the fever will decrease by about 7 days. And symptoms will begin to improve
coma and death occur in 7-14 days
Or patient who recover have permanent disability due to brain damage.
Most infected people develop mild Japanese encephalitis symptoms or no symptoms at all.
In people who develop a more severe disease, Japanese encephalitis usually starts as a flu-like illness, with:
Fever
Chills
Tiredness
Headache
Nausea
Vomiting.  
Confusion and agitation can also occur in the early stage.
SYMPTOMS

14. JAPANESE ENCEPHALITIS VIRUS:
STRUCTURE

15. HOST
Animal host Pigs are a major source of reservoir of JE virus. Infected pigs do not show any overt symptoms of illness and can transmit the virus to human beings through mosquito bites. The pigs are considered as “Amplifiers” of the virus.
Birds Pond herons, cattle egrets, poultry ducks ardeid birds appear to be involved in the natural history of JE virus.
Mosquito vectors C. Vishnui, C. pseudovishnui, C. tritaeneorhynchus, C. gelidus are the known vectors of JE virus.
Animal host
Birds
Mosquito vectors
Breeding places of mosquitoes
Irrigated rice fields
Shallow ditches.
Pools and standing water.

16. LIFE CYCLE

17. REPLICATION

18. TRANSMISSION
There is no man to man transmission. Man is only an accidental and dead end host.
Children below the age 15 are often victims of the disease

19. DIAGNOSIS
JE is diagnosed by detection of antibodies in serum and CSF (cerebrospinal fluid) by IgM capture ELISA
Viral antigen can also be shown in tissues by indirect fluorescent antibody staining

20. TREATMENT No treatment Fluids are given to decrease dehydration
Medication to decrease fever and pain
Medication to decrease brain swelling

21. PREVENTION
Personal protective measures and mosquito elimination are the most important
Control mosquito population with insecticides
Avoid contact with mosquitoes

22. REFERENCES
japanese-encephalitis-epidemiology-diagnosis-treatment-and-prevention.htm#H3
emedicine.medscape.com/article/ overview