Arbo viral diseases

Arbo Viral Diseases - By Dr. Sujatha Sathananthan

1. Arbo viral Diseases Dr. Sujatha Sathananthan MD.,DPH., Assistant Professor Department of Community Medicine Chengalpattu Medical College

2. Arthropod-Borne Viruses Ar thropod Bo rne Viruses ( Arbo Viruses) are viruses that can be transmitted to man by arthropod vectors. 12 May 2018 2 Chengalpattu Medical College

3. Arbovirus – Clinical Syndromes Febrile Group Haemorrhagic Group Encephalitis Group Chikungunya , Dengue Chikungunya Dengue KFD Yellow Fever ZIKA (NEWLY EMERGING) JE 12 May 2018 3 Chengalpattu Medical College

4. Arboviruses in India1 COMMON : Dengue V Japanese Encephalitis V Chikungunya V Kyasunur Forest Disease V Group A (Alpha virus) Chikungunya Sindibis Group B ( Flavi virus ) Dengue JE KFD West Nile Fever 12 May 2018 4 Chengalpattu Medical College

5. Virus Reservoir Vector Disease Chikungunya Monkeys Mosquito Chikungunya fever Dengue Monkeys, Man Mosquito Dengue haemorrhagic fever Japanese B encephalitis Wild birds, pigs Mosquito Encephalitis Kyasanur forest disease Forest birds, animals Tick Haemorrhagic fever Arboviruses prevalent in India 12 May 2018 5 Chengalpattu Medical College

6. Dengue Dengue is a acute febrile illness caused by arboviruses 4 antigenically distinct serotypes (DENV 1,2,3,4), transmitted by Aedes mosquitoes ( Aedes aegypti ) Aedes mosquito also transmits chikungunya , yellow fever and Zika infection May present as 1. “Classical” Dengue fever or 2. DHF without shock or 3. DHF with shock also called as Dengue Shock Syndrome (DSS). 12 May 2018 6 Chengalpattu Medical College

7. Problem statement 2.5 billion people are at risk of the disease in the tropical and subtropical countries 50 million dengue infections occur worldwide annually 5lakh people with DHF require hospitalization each year Approximately 90% of them are children <5 years and about 2.5% of these will die. 12 May 2018 7 Chengalpattu Medical College

8. Categories based on endemicity - South East Asian Region Category A – India , Bangladesh , Indonesia , Maldives, Myanmar , Srilanka , Thailand and Timor-Leste Major public health problem Leading cause of Hospitalization and death among children Hyper endemicity with all 4 serotypes circulating in urban areas Spreading to rural areas 12 May 2018 8 Chengalpattu Medical College

9. Categories based on endemicity Category B : Bhutan , Nepal Endemicity uncertain Category C : DPR Korea No evidence of endemicity 12 May 2018 9 Chengalpattu Medical College

10. Dengue on the Globe Highly endemic Recently acquired 12 May 2018 10 Chengalpattu Medical College

11. Dengue on the Globe- 2015 Philippines- 1,08,263 cases with 317 deaths Malaysia- 96,222 cases of with 263 deaths Singapore- 7,815 cases China - 1917 cases Australia - 1,393 cases The Island of Hawaii, United States of America, was affected by an outbreak with 181 cases reported in 2015 and ongoing transmission in 2016. Source- WHO 12 May 2018 11 Chengalpattu Medical College

12. DENGUE - INDIA The risk of dengue increases in recent years due to 1. rapid urbanization 2. life style changes and 3.deficient water management including water storage practices in urban, peri -urban and rural areas This all leads to proliferation of mosquitoes breeding sites 12 May 2018 12 Chengalpattu Medical College

13. Dengue cases double in  2015 (INDIA) 2014- 10,097, with 37 deaths 2015- 19,704 cases with 41 deaths CITIES Delhi- 1259 cases Bengaluru - 1139 cases Mumbai – 306 cases Kolkata – 187 cases Delhi- dengue has become a hyper-endemic due to co-circulation of different subtypes. There have been cases of the same person being infected by two different serotypes .   12 May 2018 13 Chengalpattu Medical College

14. Dengue cases in Tamil Nadu, 2015 Dengue cases double this year in Tamil Nadu Total - 2,357 cases with 5 deaths Of which 80 cases from Chennai ( Adyar , Kodambakkam and Alandur zones) High risk districts - Tirupur , Trichy , Theni , Salem, Dharmapuri and Krishnagiri districts In 2014 - 1,146 cases Tamil Nadu takes 2nd place in dengue numbers after Maharashtra 12 May 2018 14 Chengalpattu Medical College

15. Dengue cases in India 2016 (till oct 18 ) State : West Bengal- 6933 cases (25 deaths) Orissa - 6963 cases (11 deaths) Kerala - 5988 cases (10 deaths) Karnataka- 4556 cases (8 deaths) Maharashtra – 4033 cases (4 deaths) Delhi – 2122 cases (4 deaths) Tamil Nadu – 1752 cases (4 deaths) Source- NVBDCP 12 May 2018 15 Chengalpattu Medical College

16. Dengue cases in Tamil Nadu, 2016 Total – 1752 cases and 4 deaths Thiruvallur Coimbatore Kanchipuram Thiruporur 12 May 2018 16 Chengalpattu Medical College

17. Epidemiological Triad The Host The Agent(Virus) The Environment Interaction 12 May 2018 17 Chengalpattu Medical College

18. The Agent Dengue Virus 12 May 2018 18 Chengalpattu Medical College

19. The Dengue Virus Flavivirus Single stranded RNA virus 40 to 50 nanometers Arthropod borne Four sero -sub types - DENV-1, DENV- 2, DENV-3, DENV-4 12 May 2018 19 Chengalpattu Medical College

20. The Vector Aedes aegypti (Infected Female Mosquito ) (also Aedes albopictus ) 12 May 2018 20 Chengalpattu Medical College

21. AEDES MOSQUITO Tiger mosquito – White stripes on black body It is a day biting mosquito when normally coils, repellents, nets etc are not used It breads in fresh water around homes Lays eggs preferentially in manmade containers water jars, coconut shells, old tires, cement tanks, overhead tanks, discarded containers, etc, in which water stagnates for more than a week Can transmit trans- ovarially the infection in mosquitoes. It is an urban vector 12 May 2018 21 Chengalpattu Medical College

22. 12 May 2018 22 Chengalpattu Medical College

23. BREEDING SOURCES 12 May 2018 23 Chengalpattu Medical College

24. Breeding Sources 12 May 2018 24 Chengalpattu Medical College

25. Breeding sources 12 May 2018 25 Chengalpattu Medical College

26. Peculiarities of A.aegypti Highly domesticated, Strongly anthropophilic , Nervous feeder - it bites more than one host to complete one blood meal Discordant species - it needs more than one feed for completion of gonotropic cycle This habit results in the generation of multiple cases . 12 May 2018 26 Chengalpattu Medical College

27. Peculiarities of A.albopictus Aedes albopictus partly invades peripheral areas of urban cities. It is aggressive feeder Concordant species - the species can complete its blood meal in one person and also does not require a second blood meal for completion of gonotropic cycle) 12 May 2018 27 Chengalpattu Medical College

28. Host factors All ages and sexes are affected Children usually suffer from a milder illnesss when compared to adults Males suffer more often 12 May 2018 28 Chengalpattu Medical College

29. Environmental factors The population of A.aegypti fluctuates with rainfall and water storage Relative humidity - 60 to 80% Temperature - between 16 to 30 deg C 12 May 2018 29 Chengalpattu Medical College

30. Dengue virus A factor complicating eradication of the vector mosquito is that the Ae. Aegypti eggs can withstand long periods of desiccations (dry environments), sometimes for more than a year. Dengue virus elimination is not possible Mosquito transmit dengue virus ( transovarian ) in to the eggs so next generation of mosquito by birth are infected with virus Mosquito eradication is difficult Eggs survive more than 1 year period 12 May 2018 30 Chengalpattu Medical College

31. Mosquito once infected, it remains infective for its life, transmitting the virus to susceptible individuals. Dengue virus Sources Mosquito infective for its life Dengue Life Cycle 12 May 2018 31 Chengalpattu Medical College

32. Spectrum of disease 12 May 2018 32 Chengalpattu Medical College

33. Criteria for clinical Diagnosis Dengue Fever : Probable Diagnosis: Acute febrile illness with 2 or more of the following’ Headache Retro orbital pain Myalgia Arthralgia / bonepain Rash Hemorrhagic manifestations Leucopenia (WBC <= 5000 cells /cubic mm) Thrombocytopenia (platelet count <150000cells/cubic mm) Raising Hematocrit (5-10%) And atleast one of the following: Supportive serology on single serum sample : Titre >= 1280 with Haemagglutination Inhibition Test, comparable IgG titre with ELISA assay or test positive in IgM antibody test Occurence at the same location and time as confirmed cases of Dengue fever 12 May 2018 33 Chengalpattu Medical College

34. Confirmed Diagnosis- Dengue Fever Probable case with at least one of the following: Isolation of Dengue virus from serum, CSF, autopsy sample Fourfold or greater increase in serum IgG by ( Haemagglutination inhibition test) or increase in antibody specific to Dengue virus Detection of dengue virus or antigen in tissue , serum or CSF by immuno histo chemistry, immunofluorescence or ELISA Detection of dengue virus genomic sequences by RT - PCR 12 May 2018 34 Chengalpattu Medical College

35. Dengue Hemorrhagic Fever All of following : Acute onset of Fever of 2 to 7 days duration Haemorrhagic manifestations, shown by any of the following : Positive torniquet test petechiae , ecchymoses or purpura or bleeding from mucosa,GIT,injection sites Platelet count <= 100000cells/cubic mm Objective evidence of plasma leakage due to increased vascular permeability shown by any of the following : Raising haematocrit / haemoconcentration >= 20% from baseline or evidence of plasma leakage such as pleural effusion, ascites or hypo proteinaemia / albuminaemia 12 May 2018 35 Chengalpattu Medical College

36. Dengue Shock Syndrome Criteria for Dengue haemorrhagic Fever with signs of shock including: Tachycardia, cool extremities , delayed capillary refill,weak pulse , lethargy or restlessness, which may be a sign of reduced brain perfusion Pulse pressure <=20 mmHg with increased diastolic pressure Hypotension by age , defined as systolic pressure <80 mmHg for those aged <5 years or 80-90 mmHg for older children and adults 12 May 2018 36 Chengalpattu Medical College

37. Laboratory Diagnosis 1.Virus Isolation : Specimen taken with in 6 days of illness and processed without delay Acute phase serum , plasma or washed buffy coat from the patient , autopsy tissue (liver , spleen , LN and thymus) and mosquitoes collected from the affected areas. 2.Viral Nucleic acid detection : RT-PCR assay 3.Immunological Response and Serological tests: HIA ( Haemagglutination Inhibition Assay) Complement Fixation Neutralization test IgM Capture ELISA Indirect IgG ELISA and IgM / IgG ratio 12 May 2018 37 Chengalpattu Medical College

38. Laboratory Diagnosis 4.Viral Antigen Detection : ELISA and Dot Blot Assays - envelope/ Membrane antigens Non Structural Protein 1 (NS1) – can be detected up to 6 days after the onset of illness It donot differentiates between the serotypes Early diagnostic marker for clinical management. 5. RDT : serological test kits for anti dengue IgM and IgG antibodies , results with in 15 minutes . 6. Analysis of Haematological parameters: Platelet count Haematocrit values 12 May 2018 38 Chengalpattu Medical College

39. 12 May 2018 39 Chengalpattu Medical College

40. WARNING SIGNS No clinical improvement or worsening of the situation just before or during the transition to afebrile phase or as the disease progresses. Persistent vomiting, not drinking . Severe abdominal pain. Lethargy and/or restlessness, sudden behavioural changes . Bleeding: Epistaxis, black stool, haematemesis , excessive menstrual bleeding, darkcoloured urine ( haemoglobinuria ) or haematuria . Giddiness . Pale, cold and clammy hands and feet. •Less/no urine output for 4–6 hours. 12 May 2018 40 Chengalpattu Medical College

41. Home care advise for the patient Adequate bed rest Adequate fluid intake (>5 glasses for average-sized adults or accordingly in Children) Milk, fruit juice, ORS Take paracetamol Tepid sponging Look for Mosquito breeding places in and around the Home and eliminate them. Educate them on the warning symptoms. 12 May 2018 41 Chengalpattu Medical College

42. Admit the patient Existing warning signs Plasma leakage with shock and / or fluid accumulation with respiratory distress Bleeding manifestations like epistaxis, hemetemesis , malena , increased menstrual bleeding, haematuria , bleeding gums Coexisting conditions such as pregnancy, infancy, Children, Old age, diabetes, mellitus, renal failure, COPD, immune supressed 12 May 2018 42 Chengalpattu Medical College

43. T reatment protocol? Control temperature Oral fluids or intra venous fluids platelet transfusion / red cell transfusion Other supportive therapy 12 May 2018 43 Chengalpattu Medical College

44. Discharge Criteria Clinical – No fever for 48 hours Improvement in clinical status (general well-being, appetite, haemodynamic status, urine output, no respiratory distress) Laboratory – Increasing trend of platelet count (> 50000/cubic mm). Stable haematocrit without intravenous fluids 12 May 2018 44 Chengalpattu Medical College

45. Control Vector control- Removal of Breeding sources , anti larval and anti adult measures Management of roof tops , porticos and sunshades , proper covering of stored water , observation of weekly dry day Vaccination- no satisfactory measure available in India DENGAVAXIA – Sonafi –Pasteur –French company , vaccine approved – 11 countries: indonesia , thailand , singapore , mexico , philippines,brazil , peru , el salvador , costa rica , paraguay , guatemala . Individual protection- wearing full sleeves, full pants , repellant creams , coils , mosquito nets 12 May 2018 45 Chengalpattu Medical College

46. 12 May 2018 46 Chengalpattu Medical College

47. Chikungunya fever 12 May 2018 47 Chengalpattu Medical College

48. Chickungunya fever Group A virus Aedes agypte mosquitoes First isolated – Tanzania Epidemic – 1952 Doubling up 2006 – India , 1.39 million cases occurs in rainy season 12 May 2018 48 Chengalpattu Medical College

49. Cycle of Infection 12 May 2018 49 Chengalpattu Medical College

50. Chickungunya fever Incubation period :4-7 days Clinical features: fever , chills, cephalagia , anorexia, lumbago and CONJUNCTIVITIS Adenopathy , Morbilliform rash (60-80%), occasionally purpura , on the trunk and limbs Cutaneous eruptions recur every 3 to 7 days. Coffee coloured vomiting, epistaxis and petechiae Arthropathy - pain ,swelling , stiffness Metacarpophalengeal , wrist ,elbow, shoulder , knee , ankle and metatarsal joints Appears between 3 rd and 5 th day after the onset of clinical symptoms Persists for many months and even years. No deaths have been attributed to chikungunya 12 May 2018 50 Chengalpattu Medical College

51. Chickungunya fever Diagnosis : Serological diagnosis – most commonly used ELISA – to detect IgM RT-PCR 12 May 2018 51 Chengalpattu Medical College

52. Chickungunya fever Treatment: Usually self limiting Only supportive treatment Analgesics , Anti Pyretics ,fluid supplementation Aspirin and steroids to be avoided No Vaccine 12 May 2018 52 Chengalpattu Medical College

53. Chickungunya fever Vector Control: Aedes mosquito- eliminate the breeding places Abate – larvicide,prevents breeding upto 3 months Anti adult measures: aerosol spray of Ultra low volume (ULV) quantities of Malathion or Sumithion (250 ml / hectare)- effective in interrupting the transmission and stops the Epidemic of DHF Tiny droplets kill mosquitoes in air as well as in water. 2 ULV treatments 10 days apart – reduces mosquito density >98% for several weeks 12 May 2018 53 Chengalpattu Medical College

54. Japanese Encephalitis Japanese Encephalitis 12 May 2018 54 Chengalpattu Medical College

55. Japanese encephalitis(JE) is a mosquito-borne encephalitis caused by group B arbovirus ( Flavivirus ) It is a zoonotic disease, the reservior being pigs and cattle,transmitted accidentally to human beings,by the bite of infective,female,culex mosquito. INTRODUCTION 12 May 2018 55 Chengalpattu Medical College

56. Japanese Encephalitis is an Public health importance, because of its epidemic potential, high case fatality rate,   permanent sequelae , no treatment   and it is preventable. J.E. is primarily a disease of rural,semi urban, agricultural areas where vector mosquitoes proliferate in close association with pigs and other animal reservoirs.  Recent estimated 68,000 cases of JE occur globally each year,with 20,400 deaths .   12 May 2018 56 Chengalpattu Medical College

57. JE ENDEMIC AREAS IN INDIA 57 JE affected areas Andhra Pradesh Assam Bihar Haryana Kerala Karnataka Maharashtra Manipur Tamil Nadu Uttar Pradesh West Bengal 12 May 2018 Chengalpattu Medical College

58. AREA OF HIGH OCCURRENCE The three southern states of Tamil Nadu (TN), Andhra Pradesh, Karnataka were reporting higher incidence. JE is emerging as a public health problem in Kerala In a few villages of Cuddalore district of Tamil Nadu, a known JE-endemic area (Chidambaram, Virudhachalam , Thittakudi ) 12 May 2018 58 Chengalpattu Medical College

59. TAMILNADU In the early cases were reported from Tamilnadu in the following revenue districts Tiruvannamalai , Dharmapuri , Namakkal , Trichirapalli , Dindigul , Theni , Madurai,Virdhunagar , Tirinelveli ,  and Tuticorin . However for the past 5 years sporadic cases are reported from Villupuram , Cuddalore,and Perambalur districts only . 12 May 2018 59 Chengalpattu Medical College

60. 60 Tamilnadu Japanese Encephalitis –Endemic Districts 12 May 2018 Chengalpattu Medical College

61. Agent Factor Agent : Arbo virus(JE virus) belong to family Flavo -virus. It is a ss RNA virus,positive sense,non-segmented,envelped virus. It has three proteins A) Envelope glycoprotein B) Core protein and C) Membrane lipid protein. It is an an neurotropic virus. 12 May 2018 61 Chengalpattu Medical College

62. Natural host and Reservior Chief reservior -Animals(pigs and cattle) and water birds. Pigs are called as ‘Amplifier host ’ because infected pigs do not manifest any symptoms but circulate the virus so that mosquitoes get infected and can transmit the virus to man.They help only in multiplication of virus. Cattle –neither suffer nor act as amplifier host.They are only the next attractants. Horse-the only animal which develop manifestation of encephalitis. Birds – ardeid birds,pond -herons and poultry ducks 12 May 2018 62 Chengalpattu Medical College

63. Human Reservior They are the only active clinical cases and subclinical cases. Even the cases do not act as source of infection because of short period of viraemia and low level of circulating viruses. For symptomatic JE case, there are likely to be about 300 – 1000 people infected with JE virus but without any clinical manifestation. 12 May 2018 63 Chengalpattu Medical College

64. Host Factor Affects all age groups mostly children below 15 years. Males are mostly affected than females . Mostly affects the low socio – economic group People live in close association with animals are vulnerable. 12 May 2018 64 Chengalpattu Medical College

65. Environmental Factor Atmospheric temperature of about 20 deg.C and relative humidity 70 percent are favourable . Rice cultivation Pig rearing. Duck rearing. Availability of ponds and lakes. Movement of migratory birds . 12 May 2018 65 Chengalpattu Medical College

66. Seasonality of the disease: The Japanese encephalitis virus is transmitted seasonally. In temperate regions, it is transmitted during the summer and early fall, approximately from May to September. In subtropical and tropical areas, seasonal patterns of viral transmission are correlated with the abundance of vector mosquitoes and of vertebrate-amplifying hosts . These, in turn, fluctuate with rainfall, with the rainy season, and with migratory patterns of avian-amplifying hosts. 12 May 2018 66 Chengalpattu Medical College

67. Culex tritaeniorhynchus 12 May 2018 67 Chengalpattu Medical College

68. Bionomics- Culex Breeds in water polluted with organic material (refuse, excreta ) such as soak pits, septic tanks, pit latrines, shallow ditches and clean water in irrigated rice fields Biting habit They are mainly zoophilic and not anthrophilic ( i.e.they feed mainly on blood of animals and not human beings Bite through out the night Rest indoors in dark corners of rooms, shelters and hanging clothes outdoors ( exophilic ) on vegetation, tree holes and underneath culverts. 68 12 May 2018 Chengalpattu Medical College

69. Culex Extrinsic incubation period- 10 to 12 days. Once mosquito become infective,it remain infective throughout its life. Average life span-20 days. It can fly for 1 to 3 km . 12 May 2018 69 Chengalpattu Medical College

70. Clinical features Incubation period-5 to 15 days Prodromal Stage Acute encephalitic Stage and L ate stage 12 May 2018 70 Chengalpattu Medical College

71. Prodromal Stage : is characterised by Sudden onset of Fever Rigors Headache Nausea and Vomiting The duration of this stage usually lasts for 1 to 3 days. 12 May 2018 71 Chengalpattu Medical College

72. Acute Encephalitic Stage: Begins by the third to fifth day. The symptoms include: High grade fever(38-40.7 deg.C ) Neck rigidity Convulsion Altered sensorium Disorientation Progressing in many cases to coma and death 12 May 2018 72 Chengalpattu Medical College

73. Late stage and sequelae More than 50 percent of them develop neurological and psychological defecits Characterized by: Amnesia Abnormal movements,ataxia Personality changes Emotional disability Paralysis CFR varies between 20-40 per cent ,but it may reaches 80 per cent during an epidemic The average period between onset of illness and death is about 9 days 12 May 2018 73 Chengalpattu Medical College

74. JE Case Classification Suspect : a case that is compatible with the clinical description Probable : a suspect case with presumptive laboratory results Confirmed : a suspected case that is laboratory confirmed 12 May 2018 74 Chengalpattu Medical College

75. Differential Diagnosis Meningitis Febrile Convulsions Rey’s Syndrome Rabies Toxic Encephalopathy 12 May 2018 75 Chengalpattu Medical College

76. 12 May 2018 76 Chengalpattu Medical College

77. JE virus! Control and preventive measures 12 May 2018 77 Chengalpattu Medical College

78. CONTROL AND PREVENTION Vector control -Eliminate mosquito breeding areas -Adult and larval control -Personal protective measures Vaccination -Equine and swine -Humans Control of Amplifying host 12 May 2018 78 Chengalpattu Medical College

79. Vector Control Adults Larvae Indoor Residual Spray Thermal Fogging Operation Certain improvised Agricultural practice Using Neem coated urea. 12 May 2018 79 Chengalpattu Medical College

80. Larval control measures Physical method- improvement of sanitation(source reduction) by means of deweeding of ponds,removal of submerged grasses and using herbicides(shell weed killer-D) Chemical method -spraying larvicides such as abate in concentration of 1 ppm in the breeding places Biological method -using larvivorous fish such as gambusia fish Biocide method -using bacilus sphaericus which infect larvae and kill them 12 May 2018 80 Chengalpattu Medical College

81. Reduction of Breeding Source for Larvae They are water management system with intermittent irrigation system .Its a strategy of alternate drying and wetting water management system in the rice fields . Incorporation of neem products in rice fields 12 May 2018 81 Chengalpattu Medical College

82. Adult control measures Consist of indoor and outdoor spraying with insecicides such as 5% malathion or fenitrothion . All the infected villages and uninfected villages within the radius of 3 km are covered Indoor spray : Malathion is sprayed in the pigsites,catlle -shed and inside the houses,once in a fortnight for three fortnights 12 May 2018 82 Chengalpattu Medical College

83. Adult control measures Outdoor spray : This consist of a technique called ULV- fogging, wherein the insecticide malathion is heated to vapour at high temperature in a special machine The vapour after coming out,comes in contact with the moisture of cooler air and forms a fine fog,which when comes in contact with the mosquitoes,destroy them.It is called ‘ Dry fogging ’. Methods : 1.Ground level application technique 2.Aerial application technique 12 May 2018 83 Chengalpattu Medical College

84. Ground level application technique: The special machine is employed called TIFA machine .It is fitted to the open jeep vehicle. When malathion is heated and vapours start coming out, the vehicle carrying the machine is driven slowly at a speed of 5 to 6 km per hour on the roads of the villages. The favorable time for fogging is early morning or late evening,because the air is cool and form fine fog. The ideal atmospherc temperature is about 20 deg.C The output of the vehicle is about 130 litres of malathion per hour 12 May 2018 84 Chengalpattu Medical College

85. TIFA(TODD Insecticide Fog Applicator) 12 May 2018 85 Chengalpattu Medical College

86. Aerial application technique This is done by using a special single engine,single seated monoplane air craft called ‘ Basant Agriculture Air Craft’,which is used for ULV-fogging over the paddy fields It flies about 40 meters above the ground level,at a stretch of about one and half hours Three such applications,on 1,3 and 12 day respectively,are necessary for satisfactory control of mosquitoes 12 May 2018 86 Chengalpattu Medical College

87. Prevention of Mosquito Bites 87 Avoid going to rural area during dusk and dawn when the mosquitoes are most active Wear light- coloured , long-sleeved clothing and trousers Apply DEET-containing mosquito-repellents over exposed parts of the body and clothes every 4 to 6 hours For DEET products used by children, its concentration should be less than 10% 12 May 2018 Chengalpattu Medical College

88. Prevention of Mosquito Bites 88 mosquito nets hang mosquito screens around your bed, use insecticides o r coils to repel mosquitoes Install mosquito nets to doors and windows so that mosquitoes can’t get in 12 May 2018 Chengalpattu Medical College

89. Control of amplifying host Pig control has been attempted in 3ways: segregation, slaughtering or vaccination. Segregation is not practical in many settings. Slaughtering has a high economic impact and affects the livelihood of many families. Vaccination of pigs is costly, difficult and very time consuming. 12 May 2018 89 Chengalpattu Medical College

90. Vaccine availability Currently, there are three types of JE vaccines in large-scale use: Mouse brain-derived, purified and inactivated vaccine Cell culture-derived, inactivated JE vaccine based on the Beijing P-3 strain (only available in China and being replaced by live attenuated vaccine). Cell culture-derived, live attenuated vaccine based on the SA 14-14-2 strain of the JE virus. 12 May 2018 90 Chengalpattu Medical College

91. Vaccine Live attenuated SA-14-14-2 JE vaccine, Freeze dried and to be mixed with diluents supplied with the vaccine. Changes to transparent pink/orange after dilution. Manufacturer Chengdu Institute of Biological Products (CDIBP), China Storage +2 to +8 º C Dose Single dose (0.5ml) with AD syringe for every child. Route Injection - Subcutaneous Site Upper arm Target 1 – 15 years age group (i.e. more than 12 months till 15 years) SA-14-14-2 JE vaccine: 12 May 2018 91 Chengalpattu Medical College

92. JE Vaccination Target beneficiaries : 1-15 year age group in identified districts following prioritization Routine immunization to target children 92 12 May 2018 Chengalpattu Medical College

93. KYASANUR FOREST DISEASE 12 May 2018 93 Chengalpattu Medical College

94. History KFD was first recognized in 1957 in Shimoga district of Karnataka State in South India. Local inhabitants called the disease "monkey disease" because of its association with dead monkeys. The disease was later named after the locality- Kyasanur Forest - from where the virus was first isolated . Restricted to four districts ( Shimoga , North Kannada , South Kannada and Chikamagaloor ) in Karnataka 12 May 2018 94 Chengalpattu Medical College

95. Agent Member of group B togaviruses ( flaviviruses )- tick borne virus Antigenically related to other tick-borne flaviviruses . particularly the Eastern tick-borne encephalitis and Ormsk haemorrhagic fever. Unlike in many other arbovirus infections . KFD has a prolonged viremia:10 days or more . 12 May 2018 95 Chengalpattu Medical College

96. Natural hosts & reservoirs Small mammals particularly rats and squirrels -main reservoirs of the virus . Birds and bats are less important Amplifying hosts: monkeys Not effective maintenance hosts because most of them die from KFD infection. Cattle: Provide Haemaphysalis ticks with a plentiful source of blood Thus cattle are very important in maintaining tick population but play no part in virus maintenance . Humans: incidental or dead-end host , 12 May 2018 96 Chengalpattu Medical College

97. Vector The virus has a complex life cycle involving a wide variety of tick species At least 15 species of hard ticks of species Haemaphysalis , particularly H. spinigera and H. turtura Also isolated from soft ticks (not in India) Monkey infections occur during drier months, from January to June. -This period coincides with the peak nymphal activity of ticks. 12 May 2018 97 Chengalpattu Medical College

98. Host factors Age : -Majority of cases affected were between 20 & 40 years Sex : Attack rate was greater in males Occupation : -Cultivators who visit forests accompanying cattle -Wood cutters Human activity : -The epidemic correlates well with the period of greatest human activity in the forest, i.e., from January until the onset of rains, in June 12 May 2018 98 Chengalpattu Medical College

99. Transmission The transmission cycle involves mainly monkeys The disease is transmitted by the bite of infective ticks especially nymphal stages. There is no evidence of human to human transmission. 12 May 2018 99 Chengalpattu Medical College

100. 12 May 2018 100 Chengalpattu Medical College

101. Clinical features Incubation period: 3 to 8 days Sudden onset of fever, headache and severe myalgia, with prostration Acute phase: lasts for about 2 weeks Severe cases: -Gastrointestinal disturbances -Hemorrhages from gums , stomach and intestine , Second phase: -Mild meningoencephalitis after an afebrile period of 7 to 21 days -Return of fever, severe head ache, followed by neck stiffness, coarse tremors, abnormal reflexes and mental disturbances. Case fatality rate: 5 to 10 per cent Diagnosis :Isolation of the virus in the blood and/or serological evidence. 12 May 2018 101 Chengalpattu Medical College

102. Control Control of ticks: For control of ticks in forests, -application can be made by power equipment or by aircraft-mounted equipment to dispense carbaryl , fenthion , naled or propoxur at2.24 kg of active ingredient per hectare -The spraying must be carried out in "hot spots i.e ., in areas where monkey deaths have been reported . - 50 metres around the spot of the monkey deaths, besides : endemic foci. Restriction of roaming cattle in forests Vaccination: Killed KFD vaccine Personal protection: repellents like dimethyl phthalate, DEET; adequate clothing; examine the body for tick and remove them;habit of sitting or lying down on the ground shoud be discouraged 12 May 2018 102 Chengalpattu Medical College

103. 12 May 2018 103 Chengalpattu Medical College

104. Zika Virus An arthropod-borne virus (arbovirus ). A member of the  Flavivirus  genus in the family  Flaviviridae. It is related to other pathogenic vector borne flaviviruses including Dengue , Yellow fever West Nile Japanese encephalitis viruses. 12 May 2018 104 Chengalpattu Medical College

105. Name origin It owes its name from Zika Forest of Uganda, where it was first isolated in 1947 . The infection, known as  Zika Fever . In humans it was first identified in 1952 in Uganda and United Republic of Tanzania and the virus was first isolated in Nigeria in 1968 . The sporadic cases of infection were reported in Southeast Asia and Sub-Saharan Africa. 12 May 2018 105 Chengalpattu Medical College

106. Systematic Classification of Zika Virus Group IV ((+)ssRNA) Group Flaviviridae Family Flavivirus Genus Zika virus Species 12 May 2018 106 Chengalpattu Medical College

107. Zika virus Zika virus was first isolated in 1947 from the blood of a Rhesus monkey in Zika forest, in Uganda Subsequently, the virus was recovered from humans and mosquitoes in Uganda, Senegal, Nigeria, Ivory Coast, the Central African Republic and Malaysia. An outbreak of Zika virus was reported in 2007 on Yap Island of Micronesia Another outbreak in the Pacific was reported in French Polynesia in 2013 and later spread to New Caledonia In 2015, Zika virus emerged in South America with further spread across the Americas. 12 May 2018 107 Chengalpattu Medical College

108. Recent outbreak ZIKA virus moved out of Asia and Africa and caused an epidemic in YAP islands of Micronesia (2007) and French Polynesia, New Caledonia, The Cook Islands and in Easter Islands in 2013 and 2014. In 2015 there has been an upsurge in ZIKA infection dramatically in America with Brazil being most affected; 444,000 to 1.3 million cases reported through December 2015. It has been reported that ZIKA infection has spread to 23 countries across America. 12 May 2018 108 Chengalpattu Medical College

109. ZIKA Aedes albopictus was identified as the primary vector for ZIKA transmission during 2007 Gabon outbreak Sexually transmitted 12 May 2018 109 Chengalpattu Medical College

110. Pathogenesis Mosquito-borne flaviviruses are thought to replicate initially in dendritic cells near the site of inoculation. Then spread to lymph nodes and the bloodstream. Although flaviviral replication is thought to occur in cellular cytoplasm, one study suggested that Zika Virus antigens could be found in infected cell nuclei. 12 May 2018 110 Chengalpattu Medical College

111. Incubation period The incubation period of Zika virus disease is not clear, but is likely to be 3-12 days . 12 May 2018 111 Chengalpattu Medical College

112. Signs and symptoms Only 20-25% of people infected with Zika virus develop symptoms. The most common symptoms of this infection are: Headache mild Fever Skin rashes ( exanthema) Conjunctivitis Muscle and joint pain Malaise 12 May 2018 112 Chengalpattu Medical College

113. 12 May 2018 113 Chengalpattu Medical College

114. Alerts are being issued warning of the Aedes aegypti mosquito, carrier of the Zika virus which might cause microcephaly and Guillain-Barré syndrome , a condition that causes the immune system to attack one’s own nerves. 12 May 2018 114 Chengalpattu Medical College

115. Diagnosis of zika virus Polymersase Chain Reaction : Nucleic acid detection by reverse transcriptase-polymerase chain reaction (RT-PCR ). Nucleic Acid Amplification Test : Nucleic acid amplification test (NAT) for detection of viral RNA can also be performed . Plaque Reduction Neutralization Assay The Plaque reduction neutralization assay generally has improved specificity over immunoassays, but may still yield cross-reactive results in secondary flavivirus infections. 12 May 2018 115 Chengalpattu Medical College

116. Diagnosis of zika virus (cont.,) Serological Tests : An ELISA has been developed to detect IgM to ZIKV only after five days. NS1 antigen can be detected by ELISA in acute phase specimens Important Note !!!!!! IgM antibodies against Zika virus, dengue viruses, and other flaviviruses have strong cross-reactivity which may generate false positive results in serological tests. 12 May 2018 116 Chengalpattu Medical College

117. Treatment No specific vaccine or medications are available to prevent or treat ZIKA virus infections 12 May 2018 117 Chengalpattu Medical College

118. Prevention and control of zika virus Avoid travel to areas with an active infestation . Reducing mosquito populations through source reduction (removal and modification of breeding sites )   Reducing contact between mosquitoes and people through: wearing clothes (preferably light-coloured) that cover as much of the body as possible using physical barriers such as window screens closed doors and windows sleeping under mosquito nets  Using r epellents   Safer sexual practices 12 May 2018 118 Chengalpattu Medical College

119. W orld H ealth O rganization has declared the Zika outbreak a global health emergency 12 May 2018 119 Chengalpattu Medical College

120. YELLOW FEVER

121. Disease Background First account of sickness diagnosed as YF occurred in 1648. Causative agent: genus Flavivirus. Vector: Aedes aegypti (mosquito). Nonhuman primates maintain disease. 12 May 2018 121 Chengalpattu Medical College

122. Global Distribution In 45 countries of Africa & Latin America. More than 900 million people are at risk. 200,000 cases & 30,000 deaths worldwide each year. 12 May 2018 122 Chengalpattu Medical College

123. EPIDEMIOLOGY Flavivirus Fibricus Man (>24 C and >60% Humidity) YELLOW FEVER 12 May 2018 123 Chengalpattu Medical College

124. Agent Flavivirus Fibricus Group B Arbovirus 12 May 2018 124 Chengalpattu Medical College

125. Reservoir & Vector Monkey Aedes Mosquito 12 May 2018 125 Chengalpattu Medical College

126. Host Factor All ages & both sexes Persons in contact with forests. Wood cutters, Hunters. Immunity- One attack of yellow fever gives lifelong immunity. 12 May 2018 126 Chengalpattu Medical College

127. Environmental Factor Climate Tropical with a relative humidity. Endemic presence of disease in the jungle. Social Factors Urbanization, More Populated, Forest. 12 May 2018 127 Chengalpattu Medical College

128. INCUBATION PERIOD – 3-6 days PERIOD OF COMMUNICABILITY - Blood of patients is infective during the first 3-4days of illness 12 May 2018 128 Chengalpattu Medical College

129. Cycles of YF Transmission MOSQUITO MONKEY HUMAN, MONKEY MOSQUITO HUMAN HUMAN MOSQUITO MOSQUITO MOSQUITO MOSQUITO Jungle Village Urban www.who.int 12 May 2018 129 Chengalpattu Medical College

130. Clinical features Similar to viral haemorrhagic fevers More severe hepatic and renal Involvement Jaundice, haemorrhagic manifestations (black vomit, epistaxis , melena ) Albuminuria or anuria Shock , stupor, coma CFR : 80% in severe cases Survivors exhibit : life long Immunity 12 May 2018 130 Chengalpattu Medical College

131. Diagnosis & Management Serological Tests Supportive Treatment IV Fluids Antipyretics Vector control measures Use of Mosquito-net or mosquito repellents. 12 May 2018 131 Chengalpattu Medical College

132. Prevention & Control 17D Vaccine , live attenuated vaccine. Subcutaneously 0.5ml , Immunity begins to appear on the7 th day & lasts for more than 35 years. Surveillance : Aedes aegypti index <1 (house index) International Certificates- validity begins 10 days after vaccination and extends up to 10 years 12 May 2018 132 Chengalpattu Medical College

133. West Nile Fever Acute febrile illness – group B arbovirus . Endemic in India , middle east and south west asia , africa . Culex mosquitoes IP :2-14 days Sudden onset of fever, severe headache and malaise for several days. In children , maculopapular rash appears . Less than one percent cause neuro invasive disease. Fatal meningo - encephalitis is more common in older people. 12 May 2018 133 Chengalpattu Medical College

134. Pathogenic Pathway West Nile Virus Mosquito bite  virus injected into blood  Virus replicates in lymphocytes  Fever, myalgia  Virus spreads to the brain (neurons): encephalitis, headache, confusion  Slow recovery  Immunity to the virus ( One Serotype ) 12 May 2018 134 Chengalpattu Medical College

135. Diagnosis and Management Diagnosis : Real time PCR IgM and IgG ELISA Complement fixation tests Treatment: Supportive Therapy 12 May 2018 135 Chengalpattu Medical College

136. Sand fly fever 12 May 2018 136 Chengalpattu Medical College