Japanese encephalitis

japenese encephalitis is an important vector borne disease which carries a high mortality as well as high disability. it is a preventable disease and an effective vaccine is available for it.the vaccine is an important part of universal immunization program in india. Environmental modification and control of vector will go long way in the control of this disease.

1. 2/7/2019 1 Classification of Arboviral diseases and epidemiology of Japanese E ncephalitis DR. HARIVANSH CHOPRA M.D.,D.C.H. PROFESSOR, COMMUNITY MEDICINE LLRM MEDICAL COLLEGE,MEERUT

2. 2/7/2019 2 Objective to study the classification of arbo virus infections in india To study the epidemiology of JAPANESE encephalitis

3. Defined as viruses “which are maintained in nature principally, or to an important extent through biological transmission between susceptible vertebrate hosts by haematophagous arthropods”. Arbovirus (arthropod borne virus) 2/7/2019 3

4. They multiply in tissues of arthropods and passed on to new vertebrates by the bite of arthropod after a period of EXTRINSIC INCUBATION. 4 2/7/2019

5. The no of arbovirus known in I ndia had risen from two in1951(dengue and sand fly fever) to over 40 in1975 of which more than 10 are known to produce human disease. 2/7/2019 5

6. Family Genus Important species Togaviridae Alphavirus Chikungunya , sindbis Flaviviridae Flavivirus Japanese encephalitis, Yellow fever, Dengue type 1,2,3,4,K F D Bunyaviridae Phlebovirus Sandfly fever virus , Rift vally fever virus Reoviridae Orbivirus African horse sickness Rhabdoviridae Vesiculovirus Vesular stomatitis virus,Chandipura virus Some Arbovirus known to be prevalent 2/7/2019 6

7. 2/7/2019 7 Group A (ALPHA VIRUSES) Sindbis chikungunya Group B ( Flaviviruses ) K F D,JE,WEST NILE FEVER OTHERS Umbre,Sathuperi,Chandipura , Chittor,Ganjam,Minnal,Kaisodi , Dengue,sandfly fever,African horse Sickness , vellore,venkatpuram Some Arbovirus known to be prevalent in india

8. 2/7/2019 8 Only small number of arbo viruses can produce disease and three clinical syndromes have been identified A FEBRILE GROUP characterized by the presence of fever With or without rashes and joint pains CLINICAL SYNDROMES

9. 2/7/2019 9 HAEMORRHAGIC Characterised by the presence of haemorrhagic fevers and high mortality like KFD, DENGUE HAEMORRHAJIC FEVER CLINICAL SYNDROMES

10. 2/7/2019 10 CLINICAL SYNDROMES ENCEPHALITIDIS Characterised by the presence of meningitis and encephalitis eg JAPANESE encephalitis

11. It is a mosquito- borne encephalitis caused by flavivirus and transmitted by culicine mosquito. Its a zoonotic disease i.e. infecting mainly animals and incidently man. Japanese encephalitis 2/7/2019 11

12. JE is the leading cause of viral encephalitis in Asia and occurs in almost all Asian countries. Increasing no of cases are reported from Bangladesh, India, Nepal, Pakistan ,Thailand and Vietnam. MAGNITUDE 2/7/2019 12

13. Estimated 50,000 case occur globally each year, with 10,000 deaths and nearly 15,000 disabled. About 85% cases are children of less than 15 years of age. MAGNITUDE 2/7/2019 13

14. JE was first Serologically recognised in 1955 in Tamil Nadu . Disease is endemic in 14 state . In India about 300 million population is at risk . During 2011, 7,838 cases and 1,137 deaths were reported. Problem in India 2/7/2019 14

15. 2/7/2019 15 C Cases of JE in india

16. DEATHS DUE TO J E IN INDIA 16

17. Basic cycle of transmission are: A) Pig → mosquito → pig B) The Ardeid bird → mosquito → Ardied bird Man is an incidental “dead end”host . Epidemiological features 2/7/2019 17

18. Pigs are major vertebrate host and are considered as “amplifiers” of virus. Infected Pigs do not manifest any overt symptoms of illness but circulate the virus so that mosquito get infected and can transmit the virus to man. Animal hosts 2/7/2019 18

19. Cattle and buffaloes may also be infected and act as “mosquito attractants”. Birds e.g pond herons ; cattle egrets and perhaps poultry and duck appears to be involved in natural history of disease. 2/7/2019 19

20. CULEX TRITAENIORHYNCHUS CULEX VISHNUI CULEX GELIDUS Mosquito vectors 2/7/2019 20

21. 2/7/2019 21 These mosquitos generally breed in irrigated rice field, shallow ditches and pools. BREEDING PLACES

22. 2/7/2019 22 Female mosquitoes get infected after feeding on a viraemic host, and after 9-12 days incubation period ,they can transmit the virus to other host. EXTRINSIC INCUBATION PERIOD

23. Incubation period exact duration is not known varies from 5-15 days. JE in man 2/7/2019 23

24. 2/7/2019 24 Not all individual bitten by mosquitoes develop disease

25. The ratio of overt disease to in apparent infection varies from 1:300 to 1:1000. Encephalitis due to JE may show a scattered distribution. 2/7/2019 25

26. 2/7/2019 26 COURSE OF DISEASE Disease occurs in three stages Prodromal stage Acute encephalitic stage Late stage and sequelae

27. Prodromal stage- fever, headache, gestrointestinal disturbances ,lethargy, malaise .Duration 1-6 days. COURSE OF DISEASE 2/7/2019 27

28. 2/7/2019 28 Encephalitis stage- fever is usually high 38 to 40.7degc., nuchal rigidity, focal CNS sign, convulsion, difficulty in speech

29. 2/7/2019 29 dystonia , Ocular palsies, hemiplegia , quardriplegia , extra pyramidal sign, and in many cases coma .

30. Late stage and sequelae -the active inflammation is at an end i.e. the temperature and ESR touch normal. Neurological sign become stationary or tend to improve. 2/7/2019 30

31. The case fatality rate varies between 20-40 percent and may reach upto 58 percent.  but approximately 30-50 % of the surviving patients have permanent neuropsychiatric sequelae and complete recovery occurs in only one-third of patients. 2/7/2019 31

32. 2/7/2019 32 Average period between the onset of illness and death is about 9 days.

33. IgM - capture ELISA which detects specific IgM in CSF or in blood of almost all patients with in 7 days of onset of disease. Others- conventional antibody assay on paired sera, dot blot IgM assay Diagnosis 2/7/2019 33

34. Following an outbreak of JE in Gorakhpur and Basti division in eastern UP during 2005,Directorate of NVBDCP developed surveillance guidelines for endemic state and advised that all the JE cases be reported under Acute Encephalitis Syndrome. Guidelines for management of ASE 2/7/2019 34

35. Acute onset of fever,not more than 5-7 days duration. Change in mental status with / without A)New onset of seizures(excluding febrile seizures) B)Other early clinical findings including irritability, somnolence and abnormal behavior. Case definition 2/7/2019 35

36. Laboratory –confirmed case A suspected case with any one of the following markers IgM antibodies in serum / csf Four fold rise in IgG Virus isolation from brain tissue Antigen detection by immunofluroscences Nucleic acid detection by PCR Case classification 2/7/2019 36

37. 2/7/2019 37 Probable cases Suspected case in close geographic area and Temporal relationship to a lab. Confirmed case of JE/AES in an outbreak

38. 2/7/2019 38 Acute encephalitis Syndrome due to other agent A suspected case in which diagnostic testing is performed and An aetiological agent other than AES/JE is identified

39. 2/7/2019 39 Acute encephalitis Syndrome due to unknown agent A suspected case in which no diagnostic testing is performed/ no aetiological agent is indentified / Test results are indeterminate

40. MANAGEMENT OF AES INCLUDING JE AT COMMUNITY LEVEL 2/7/2019 40 FEVER → SPONGING / PARACETAMOL CONVULSION → ANTICONVULSANT SECRETION → SUCTION

41. 2/7/2019 41 Management of AES including JE At community level Indentification of danger signs A letahargy B unconsciousness C convulsions D other findings such as rash, paralysis and hepato spelenomegaly

42. 2/7/2019 42 Management of AES including JE at FRU Treatment I/V LINE Correction of blood sugar Suction and oxygen i /v anticonvulsant Use of ambu bag Decompression therapy with mannitol Monitoring of vitals

43. 2/7/2019 43 Management of AES including JE No improvement/ futher deterioration Presence of shock Cyanosis and need for ventilator Referral to tertiary Centre

44. A) Vaccination B) Vector control Control of JE 2/7/2019 44

45. Three types of vaccines 1Inactivated Cell cultured derived S A -14-14-2 vaccine Minimum age 1 year Vaccination 2/7/2019 45

46. Primary immunization 2 doses of .25 ml i /m On day 0 and 28 between 1-3years Above the age of 3 years dose is .5ml Need of booster -undetermined Vaccination 2/7/2019 46

47. 2/7/2019 47 2 VeroCell culture derived inactivated vaccine based on kolar strain 821564XY made in india by Bharat Biotech

48. 2/7/2019 48 Primary immunization Minimum age 1 year 2 doses of 0.5 ml i /m At an interval of 4 weeks Need of booster -undetermined

49. Mouse brain vaccine provide adequate immunity through out childhood following 2 primary doses 4 week apart and booster after 1 year and subsequently at 3 year until the age of 15 year. ROUTE OF ADMINISTRATION Subcutaneous Dose 0.5 ml In children < 3years and 1 ml >3years 2/7/2019 49

50. 2/7/2019 50 3 Cell culture derived-live attenuated vaccine based on SA14-14-2 strain.

51. SA-14-14-2 single dose followed by single booster at an interval of 1 year. This is an integral part of universal immunization program in 83 endemic district of UP ,Assam ,West Bengal and Karnataka in age goup 1-15 yeas. 2/7/2019 51

52. 2/7/2019 52 As per Govt. of India guidelines, 2 doses of JE vaccine have been approved to be included in UIP to be given one along with measles at the age of 9 months and the second with DPT booster at the age of 16-24 months w.e.f . April, 2013

53. Vaccination of swine is extremely important for both public health and economic reasons. 2/7/2019 53

54. Not easily amenable to control. Ground fogging with ultra low volume insecticides. Vector control 2/7/2019 54

55. 2/7/2019 55 villages with in the proximity of infected village should be kept under surveillance.

56. 2/7/2019 56 observerzparadise.com

57. 2/7/2019 57 MCQ WHICH of the following states have maximum no of cases of JE TAMIL NADU ANDRA PRADESH BIHAR UTTAR PRADESH 4

58. 2/7/2019 58 Q 2The ratio of overt disease to in apparent infection varies from 1:100 1:200 1:300 NONE OF THE ABOVE 3 MCQ

59. 2/7/2019 59 Mortality due to japanese encephalitis is in between 5-10% 10-15% 20-25% 60-70% 3 MCQ

60. 2/7/2019 60 Q.4 Age of administration of SA 14-14-2 vaccine is One year Two year Three year None of the above 4

61. 2/7/2019 61 Q.5 WHICH OF THE FOLLOWING IS THE VECTOR OF JAPANESE ENCEPHALITIS IN INDIA CULEX TRITAENIORHYNCHUS CULEX VISHNUI CULEX GELIDUS ALL OF THE ABOVE 4

62. 2/7/2019 62 conclusion Japenese encephalitis is a disease with high mortality and leaves behind a cripping disability. It can be prevented by the effective use of vaccine as well by vector control and environmental modification