JAPANESE ENCEPHALITIS phase 3.pptx oknnnn

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1. CM 8.1 Describe and discuss the epidemiological and control measures including the use of essential laboratory tests at primary care level for communicable disease (Japanese Encephalitis) Dr.Parimita Roychoudhury Assistant Professor, DMCH, Dhubri

2. LEARNING OBJECTIVES At the end of the session students will be able to 1.Define and differentiate between Acute Encephalitis syndrome and Japanese Encephalitis 2.Enumerate and Describe the epidemiological triad of Japanese Encephalitis 3.Describe the clinical features and differential diagnosis of Japanese Encephalitis 4.Describe the Laboratory diagnosis 5.Describe the Prevention and control methods of Japanese Encephalitis

3. Vector- living organism that transmits an infectious agent from an infected animal to a human or another animal a) Invertebrate type : Arthropod vector fall into 7 categories. (1) Diptera - flies and mosquitoes (2) Siphonaptera - fleas (3) Orthoptera - cockroaches (4) Anoplura - sucking lice (5) Hemiptera - bugs, including kissing bugs (6) Acarina - ticks and mites (7) Copepoda - cyclops b) Vertebrate type — Mice, rodents, bats.

4. NVBDCP NVBDCP

5. AES Any person of any age who develops acute onset of fever & change in mental status (confusion, disorientation, coma, inability to talk, new onset seizure- excluding simple febrile seizure). Cause- virus, bacteria, fungus, parasites, spirochetes, chemical/ toxins. Group of diseases having similar S/S. JE Common cause of AES. A PATIENT WILL COME WITH S/S OF AES NOT JE.

6. EPIDEMIOLOGY, PREVENTION AND CONTROL OF JAPANESE ENCEPHALITIS 7

7. INTRODUCTION 8 JE is a zoonotic disease transmitted by mosquito Case-fatality rate among those with encephalitis can be as high as 30% 24 countries in the WHO South-East Asia and Western Pacific regions have endemic JEV transmission There is no cure for the disease

8. History of JE 1870-Japan “Summer Encephalitis” epidemic 1924-Great epidemic in Japan ,case fatality 62% 1940 to 1954-Epidemic in China,Korea,India 1983-Immunization in human first started in Korea 2006 –JE vaccine introduced after campaign in endemic districts in India

9. DISTRIBUTION OF JE IN INDIA 10 ICMR

10. The disease is endemic in 21 states. Assam, Bihar, Haryana. Uttar Pradesh, Karnataka, West Bengal and Tamil Nadu report out-breaks every year and contribute about 80 per cent of cases and deaths

11. ASSAM HISTORY 1963-Serological evidence 1976- First epidemic in Upper Assam 1978- Virus isolation from Brain tissue at AMCH 1978, 1982, 1986 -Greater magnitude epidemic. Most affected districts are Dibrugarh, Dhemaji , Lakhimpur, Sivasagar , Jorhat, Golaghat , Tinsukia & Sonitpur . 12

12. ASSAM 13

13. EPIDEMIOLOGY of Japanese Encephalitis

14. Agent Family Flaviviridae Genus Flavivirus (group B Arbovirus) Genomes SS RNA Serotypes Nakayama, Beijing Temperature - Destroyed by heating for 30min above 56 degree. Chemical/Disinfectants- Inactivated by common detergents, 70% ethanol, 3-8% formaldehyde, 2% glutaraldehyde, 1% sodium hypochlorite. Sensitive to UV light and gamma irradiation. 16

15. Hosts 17 Human host- Bimodal age distribution Children & young adults (<15years)- 85% Elderly (>60years)- 10% 1 clinical case suggests 300-1000 infections Natural host Amplifier host Dead end host Ergot, heron

16. Enviroment Temperate- Late summer/early autumn Tropical- Year round Endemic in temperate & tropical regions of Asia. Epidemics- Paddy season (monsoon & post monsoon) Primarily rural areas. It has spread to new areas d/t agricultural development supported by irrigation programme 18

17. Seasonal incidence- 19 2

18. Vector 20 Culicine mosquitoes- Culex tritaeniorhynchus , Culex vishnui and Culex pseudovishnui

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20. Human to hu man transmission has not so far been recorded Man is an incidental dead-end host Cattle and buffaloes may also be infected with the JE virus; although they may not be natural hosts of JE virus, they act as " mosquito attractants” 9-12 days incubation period, they can transmit the virus to other hosts

21. CLINICAL FEATURES 23

22. PRODROMAL STAGE ACUTE ENCEPHALITIS CONVALESCENCE & SEQUELAE IP- 5-15 days Lasts- 1-6 days Nonspecific –acute fever headache malaise No CNS S/S. Fever 38 - 40.7  C Headache, muscular rigidity, seizure, nuchal rigidity. Altered sensorium, Coma. Focal CNS signs. Extra pyramidal signs ( dystonia, choreoathetosis and coarse tremors). Temp & ESR touch normal 25% develop motor and intellectual deficit. Neuropsychiatric sequel 30-50%. Case fatality rate 20-40% 24 CLINICAL FEATURES

23. LABORATORY DIAGNOSIS 25

24. LABORATORY DIAGNOSIS 26 TENTATIVE Antibody detection Heamagglutination Inhibition Test (HI), Compliment Fixation Test (CF), Enzyme Linked Immuno- Sorbant Assay (ELISA) for IgG (paired) and IgM (MAC) antibodies, etc. ELISA (Serum, CSF) Antigen Detection RPHA, IFA, Immunoperoxidase etc. Genome Detection RTPCR DEFINITIVE Virus isolation CSF, Brain IgM ELISA is the method of choice provided samples are collected 3-5(within 7 days) days after the infection

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26. DIFFERENTIAL DIAGNOSIS

27. DIFFERENTIAL DIAGNOSIS 29 Patient with fever, altered sensorium lasting more than 6 hours, no skin rash and other known causes of encephalitis excluded *Fever with rash excludes JE *AES with symmetrical signs & fever likely to be Cerebral Malaria

28. CASE DEFINITIONS

29. Field based management (case definition) 31 Suspected case Acute fever of 5-7 days + altered mental status + new seizure (except febrile) Probable case Suspected case in geographical/ temporal proximity of a confirmed case Confirmed case Suspected case with anyone- JE specific IgM 4 fold raised IgG Isolation of virus/ag/ nucleic acid AES d/t other agent Suspected case in which diagnostic test is performed and aetiological agent other than AES/JE is identified AES d/t unknown agent Suspected case in which NO diagnostic test is performed/ no aetiological agent is identified/ test results are indeterminate

30. MANAGEMENT OF CASES 32

31. WHAT HAVE WE LEARNT TILL NOW……… Viral infection Fever + Altered sensorium HOW DO WE START MANAGEMENT- History Clinical examination (General & Systemic)

32. MANAGEMENT OF CASES Symptomatic and supportive Refer to nearest FRU if anyone develops- Lethargy, Convulsions, Unconsciousness Refer to higher center directly if develops- Shock, Needs ventilator, Unmanageable cyanosis. Suspected case referred should be confirmed with 2 diagnostic test- 1. RT-PCR 2. Detection of- virus ag/ genome. 34

33. Management A, B, C, D Referral note should include history and clinal examination findings….WHY

34. The treatment of the patients may require as follow:- 1.) Management of Airways and Breathing . 2.) Management of Circulation. 3.) Control of Convulsion and Intracranial pressure 4.) Control of Temperature 5.) Fluid and Electrolytes and Calories/ Nutrition 6.) General management 7.) Specific treatment of any for treatable cause 8.) Investigations, Sample Collection & Transportation 9.) Reporting of a case 10.) Rehabilitation.

35. PREVENTION & CONTROL

36. PREVENTION & CONTROL 42 LEVELS OF PREVENTION ACTIVITES Primordial Primary IEC, vector control, Vaccination Secondary Diagnosis & Management of cases Tertiary Rehabilitation

37. PRIMARY LEVEL 43

38. Vector Control Fogging During containment of JE outbreak Anti- larval operations Environmental measures (neem as fertilizer in fields, Alternate drying & wetting water management) Larvivorous fish Gambusia affinis ,Guppy Bio larvicides Bacillus thuringiensis, Israelensis , B sphaericus 44

39. Fogging Affected village- Aerial/ground fogging with ULV insecticides (Malathion, Pyrethrum). Uninfected village- Falling within 2-3km radius of infected village. Pre requisites of fogging- Done in outdoor situations. Downwind to upwind situation. Direct to all resting sites. Medium/dry fog type. 45

40. Time of fogging- 46 9

41. Personal protective measures LLITBN- Pyrethroid Curtains Repellants Proper clothing 47

42. Control of Pig Immunization- Inactivated/ attenuated vaccines. Challenge- difficult to ensure complete coverage due to rapid breeding & limited vaccine effectiveness. Slaughtering of pig Mosquito proof piggeries Segregating pigs 4-5km away from human habitations 48

43. Vaccination in human 3 types of vaccines- Inactivated brain derived and purified type- Nakayama/ Beijing strain Cell culture derived- Inactivated- Beijing P-3 strain,Kolar 821564XY Cell culture derived- Live attenuated- SA 14-14-2 strain Recommended for- Children, Laboratory staff, Travellers (Visiting >30days) Dose & Schedule- 0.5ml for <3years, 1ml for >3years. 2 dose 1 month apart Booster- 1year, every 3 rd year till 15 years 49

44. Secondary level Field based management (Case definitions) Laboratory diagnosis Management of cases 50

45. SURVEILLANCE

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47. Periodicity of Reports- Daily report- Outbreak situation Weekly report- Transmission period Monthly report- Inter-epidemic period. Forms- AESF 1/1A- From states AESF 2/2A- Districts AESF 3- Line listing form AESF 4- Case investigation form 53

48. MORTALITY/ MORBIDITY 56 Swine High mortality in piglets. Death rare in adult pigs. Equine Morbidity- 2% during outbreak. Mortality 5%( upto 30%) Humans Mortality 5-35%. 20-40% but may reach 58% & over, higher in children. Serious neurologic sequelae 33-50%. MORTALITY MORBIDITY

49. Thank you…