This document discusses three arboviral diseases: Dengue, Chikungunya, and Kyasanur Forest Disease (KFD). Dengue and Chikungunya are transmitted by Aedes mosquitoes and cause acute febrile illness with joint pain. KFD is transmitted by ticks and found only in southern India, where it causes hemorrhagic fever with a 5-10% fatality rate. The document covers the clinical presentation, diagnosis, treatment and prevention of these diseases, emphasizing the importance of mosquito control and community cooperation to reduce transmission.

1. 1. DENGUE
2. CHIKUNGUNYA
3. KYASANUR FOREST DISEASE (KFD)
1
Dr. Sushrit A. Neelopant
Assistant Professor,
Department of Community Medicine
RIMS, Raichur

2. DENGUE FEVER
2

3. Dengue

4. SUB-CONTENTS
• Introduction
• Problem statement
• Epidemiological determinants
• Clinical manifestation
• Diagnosis
• Treatment
• Control measures
4

5. Introduction
• Acute
• Infectious
• Commonest Arboviral disease.
• Caused by dengue virus
• Transmitted by female Aedes mosquitoes
5

6. Problem statement-World
• 2.5 Bil.- at risk - Tropical & Sub Tropical regions
• 90% of affected – Children <5 years
• 2.5% of – affected - die.
• Pandemic in 1998: 1.2 million cases & 15,000 deaths
Annually:
5 crore infections,
5 lakh cases,
12 thousand deaths.
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7. • Endemic - >100 countries-
– Africa, America, Eastern Mediterranean, SEAR,
Western Pacific.
Division of SEAR - based on endemicity:
• Category A: (Bangladesh, India, Indonesia, Maldives,
Myanmar, Sri Lanka & Thailand)
• Category B: Bhutan, Nepal; Endemicity uncertain.
• Category C: DPR Korea ; No Endemicity.
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8. 8

9. pic
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10. India
• Endemic in 31 states/UT.
• An emerging public health problem with cyclical
epidemics.
Epidemics Timeline:
• 1956: 1st epidemic, Vellore, Tamil Nadu.
• 1996: Delhi-10,252 cases, 423 deaths.
• 1997: Maharashtra
• 2003: 12,750 cases, 217 deaths all over country.
• 2011: 18,059 cases, 119 deaths.
Case Fatality rate: 0.65%
• Serotypes: DENV-1,2,3,4.
• Dengue is now the MCC of fever in India  Malaria.
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11. Dengue/DHF situation in India
State 2010 2011
Cases Deaths Cases Deaths
Andhra Pradesh 776 310 1,209 6
Delhi 6,259 8 1,131 8
Chandigarh 221 0 70 0
Goa 242 0 27 0
Gujarat 2,568 1 1,693 8
Haryana 866 20 267 3
Karnataka 2,285 7 405 5
Kerala 2,597 17 1,281 10
Maharashtra 1,489 5 1,067 21
Punjab 4,012 15 3,921 6
Rajasthan 1,823 9 1,062 0
Tamil Nadu 2,051 8 2,437 9
Uttar Pradesh 960 8 147 5
West Bengal 805 1 510 0
Total 28,295 110 18,095 119 11

12. Epidemiological determinants
12

13. AGENT FACTORS
Agent & Vector
Dengue transmission
• It has 4 sero types & many sub types
• Aedes aegypti - most important
• Virus multiplies in the mosquito
• Mosquito develops life long non-cytocidal infection
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14. Dengue vectors
Aedes aegypti:
• The most important vector in Africa, America & Asia.
• Mosquito prefers peri domestic settings
• Prefer to bite during day
• Aedes aegypti has a limited flying ability-100m
• Aedes albopictus is another vector
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15. Environmental factors
15

16. Host Factors
• Children aged < 5 years(90%).
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17. Dengue- Clinical manifestation
17

18. Clinical source
• Infection may be asymptomatic, atypical, classical or
can evolve to hemorrhagic syndrome with or without
shock
18

19. Classical dengue fever
• Sudden on onset
• Fever, headache, lymphadenopathy…
• No splenomegaly
• Marked muscle pain (Break bone fever)
• Fever - biphasic
• Rashes appear on the 3rd–5th day
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20. Complicated dengue
• Dengue hemorrhagic fever (DHF)
• Dengue shock syndrome (DSS)
-Dramatic and mortality high
-Occurs mainly in children
-Development of neutralizing antibodies
20

21. DHF
• Fever
• Hemorrhagic complications ( + tourniquet test)
• Thrombocytopenia < 100000/ µl
• Signs of plasma loss
• Severity of the condition (DHF/DSS) can be given by
clinical score
21

22. Diagnosis
• Clinical signs & symptoms
• Laboratory: Thrombocytopenia, Leucopenia, Raised
haematocrit
• Serology: Dengue ICT, IgM, IgG can be detected
• ELISA
• Antigen detection
22

23. Treatment
• Symptomatic
• Paracetamol, no aspirin (risk of bleeding)
• Hemorrhagic dengue: IV infusion, fluid balance,
blood transfusion
• Platelets transfusion
• Steroids can be used but not effective
24

24. Control & prevention
• Mosquito control
-vectors of DF & DHF breeding places controlled by
individual and community action
-anti adult & anti larval measures
• Vaccine: an experimental tetravalent vaccine
• Other measures: Mosquito nets & repellents
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25. Chikungunya
26

26. Introduction
• Chikungunya
– Transmission documented in 37 countries
• Primarily found in Africa and Asia
• 1.4 million cases reported in 2006
– Travel-associated cases documented in U.S.
• 109 cases since 1995
– Similarities with dengue
• Same vectors
• Humans can become reservoirs when infected
27

27. Chikungunya
• Viral illness
• Spread by mosquitoes
• Resembles Dengue fever
• Severe persistent joint pain [arthritis]
• Fever
• Rash
• Rarely life threatening
• Morbidity & economic loss

29. Epidemiology
• India – 1824 [ Fever, rash & Arthritis ]
• Tanzania – 1952-1953 - First isolated
• Major epidemics – Cyclical
• Inter-epidemic period – 7-8 yrs[20yrs also]

30. INDIA
• Till Oct 2006 – 151 districts of 8 states/provinces
• AP, Andaman & Nicobar Islands, Tamil Nadu,
Karnataka, Maharashtra, Gujarat, Madhya Pradesh,
Kerala & Delhi.
• India total – 1.25 million cases
• Karnataka – 752245
• Maharashtra - 258998
• Attack rates – 45 %
32

31. Epidemiology:
• 1952-53: Virus isolated from human serum and
mosquitoes first time during an epidemic in Tanzania.
• 2004-06: An outbreak originating on the coast of
Kenya spread to several Indian Ocean islands and
Asia, causing millions of disease cases.
• 2007: Concern for the spread of CHIKV peaked, when
the virus was found to be spreading
autochthonously (human-to-mosquito-to-human) in
northern Italy.
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33. Epidemiological determinants
35

34. Agent Factor
• Chikungunya is an Alphavirus of the family
Togaviridae.
• It is composed of an enveloped, single-strand,
positive sense RNA genome.
36

35. • Vectors:
Aedes aegypti
Aedes albopictus
(“Asian Tiger Mosquito”)
• Hosts:
Humans are the primary
reservoir
37

36. Extrinsic and Intrinsic Incubation
Periods Of Chikungunya Virus

38. Clinical Manifestation
40

39. Chikungunya : The clinical picture
• The majority (72-97%)
of persons infected will
become symptomatic.
• Incubation Period: 3-7
days (1-12 days)
• Period of
Communicability : 3-10
days

40. Acute Disease

41. Sub acute & Chronic Disease

42. Atypical Manifestations Of CHIKV Infection

43. Diagnosis
Three main types of
laboratory tests
• Virus isolation: Within the
first 3 days of illness.
• RT-PCR: Day 1-8, after onset
of illness.
• Serological assays for
IgM/IgG: 4 days after illness
and beyond.
National Center for Emerging and Zoonotic Infectious Diseases Division of Vector-Borne Diseases

45. Virus Isolation
• Most definitive
• Sample – 2-5 ml Whole blood
• Time – 1st wk of illness
• Collection – Heparinized tube
• Transport – In Ice
• CHIK virus – Cytopathic effects in cell line – BHK-
21,HeLa & Vero Cells.
• Confirmed – CHIK specific Antiserum
• Results – 1-2 wks
• BSL-3 Labs – Reduces risk of viral transmission

46. RT - PCR
• Primer pairs amplifying specific components of 3
structural gene regions
- Capsid ( C )
- Envelope E2
- Part of Envelope E1
Results – 1-2 days
Specimen – Heparinized whole blood

47. Serological diagnosis
• Specimen – 10-15 ml whole blood sera
• Acute phase serum - Immediately
• Convalescent phase serum – 10-14 days after disease
onset
• Transported – At 4 degrees & not frozen
[immediately]
- If sera – Shipped frozen

48. Serological diagnosis
• Acute phase – 4 fold increase in Ab than
Convalescent phase
• Demonstrate IgM Ab specific for CHIK virus
- MAC-ELISA [IgM Ab Capture ELISA]
- Results – 2-3 days
- Cross reactions – O’nyong-nyong & Semliki Forest
- Confirmation – Neutralization tests & HIA

49. Existing Laboratory Network for Diagnosing
Chikungunya
Country Serological Test PCR
India National Institute of
Virology, Pune
National Institute of
Virology, Pune
Indonesia NIHRD, NAMRU-2, NIHRD ,NAMRU-2
Myanmar Department of Medical
Research
NA
Sri Lanka Medical Research
Institute
Medical Research
Institute
Thailand NIH, Bangkok, AFRIMS NIH, Bangkok, AFRIMS

50. Differential Diagnosis
• Diseases should be considered based upon
epidemiological features such as place of residence,
travel history and exposure.
• Dengue fever
• Leptospirosis
• Post-infection arthritis
• JRA

51. Management
- Not life threatening
- Symptomatic – Pain & Fever
- Rest
- Convalescence – 1 yr or more
- Persistent joint pain – Analgesic
- Long-term anti-inflammatory therapy
53

52. Treatment
Treatment: No specific antiviral drug
Acute Disease:
• Rest & Fluids
• NSAIDs (to relieve arthritic component)
Severe joint pains unresponsive to NSAIDs:
• Narcotics (e.g., morphine)
• Short-term corticosteroids
Subacute & Chronic Disease:
• Long-term anti-inflammatory therapy
• Intra-articular corticosteroids or topical NSAID
• Graduated physiotherapy

53. Prevention & Control
• No vaccine
• Prevention – Avoid Mosquito bites & Elimination of
breeding sites
55

54. • Full sleeve clothes & long dresses
• Mosquito coils, Repellents & Vapour mats
• Mosquito Nets – Babies, Old people.
• Nets & Curtains Treated with Permethrin
56

55. Prevent Mosquito breeding
• Manmade containers – Discarded tires,Flower
pots,old oil drums,animal water troughs,water
storage vessels,plastic food containers
• Eliminated by
- Draining from coolers,tanks,barrels,drums & buckets
- Emptying coolers when not in use
- Cooperating with public health authorities

56. Role of Public health authorities
• National programme – Strengthened & Efficiently
implemented
• Legislations – Enforced
• Communities – Active cooperation

57. Kyasanur Forest Disease
59

58. • Introduction
• History
• Problem statement
• Epidemiological determinants
• Clinical features
• Diagnosis & Treatment
• Prevention & control
60

59. Introduction
• Febrile disease associated with hemorrhages
• Caused by Flavi virus of Togaviridae family.
• Transmitted to man by infected hard tick bite.
• Case fatality: 5-10%
61

60. History
• First isolated in 1957 in Kyasanur forest area.
• Sagar-Sorab taluk, Shimoga district, Karnataka
• Monkeys and local village population effected
• First called as monkey disease
• Later named as Kyasanur forest disease (KFD)
• Virus isolated at NIVRC, Pune
62

61. Problem statement
• Restricted to Shimoga, North Kannada, South
Kannada & Chickamalagalur districts.
• Area coverage- 6000 sq.km
• 1983 -84 largest outbreak with 2167 cases & 69
deaths
• 2001 February: Chickamagalur district
• Deaths of monkeys considered as heralders of
disease
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62. Epidemiological determinants
64

63. Agent Factor
KFD virus:
• Group B Arbovirus,
• Family: Togaviridae,
• Genus: Flavivirus,
• RNA virus, 25-40u diameter,
65

64. Chikungunya & Dengue
• Clinical manifestations almost same
• Co-occurrence recently in Maharashtra

66. Virus Isolation
• Most definitive
• Sample – 2-5 ml Whole blood
• Time – 1st wk of illness
• Collection – Heparinized tube
• Transport – In Ice
• CHIK virus – Cytopathic effects in cell line – BHK-
21,HeLa & Vero Cells.
• Confirmed – CHIK specific Antiserum
• Results – 1-2 wks
• BSL-3 Labs – Reduces risk of viral transmission

67. RT - PCR
• Primer pairs amplifying specific components of 3
structural gene regions
- Capsid ( C )
- Envelope E2
- Part of Envelope E1
Results – 1-2 days
Specimen – Heparinized whole blood

68. Serological diagnosis
• Specimen – 10-15 ml whole blood sera
• Acute phase serum - Immediately
• Convalescent phase serum – 10-14 days after disease
onset
• Transported – At 4 degrees & not frozen
[immediately]
- If sera – Shipped frozen

69. Serological diagnosis
• Acute phase – 4 fold increase in Ab than
Convalescent phase
• Demonstrate IgM Ab specific for CHIK virus
- MAC-ELISA [IgM Ab Capture ELISA]
- Results – 2-3 days
- Cross reactions – O’nyong-nyong & Semliki Forest
- Confirmation – Neutralization tests & HIA

72. Box 1: Existing Laboratory Network for Diagnosing Chikungunya
Country Serological Test PCR
India National Institute of Virology,
Pune
National Institute of Virology,
Pune
Indonesia NIHRD, NAMRU-2, NIHRD ,NAMRU-2
Myanmar Department of Medical
Research
NA
Sri Lanka Medical Research Institute Medical Research Institute
Thailand NIH, Bangkok, AFRIMS NIH, Bangkok, AFRIMS

74. Treatment, Prevention & Control
• Treatment
- Not life threatening
- Symptomatic – Pain & Fever
- Rest
- Convalescence – 1 yr or more
- Persistent joint pain – Analgesic
- Long-term anti-inflammatory therapy

75. Prevention & Control
• No vaccine
• Prevention – Avoid Mosquito bites & Elimination of
breeding sites

76. Avoid Mosquito bites
• Full sleeve clothes & long dresses
• Mosquito coils, Repellents & Vapour mats
• Mosquito Nets – Babies, Old people.
• Nets & Curtains Treated with Permethrin

77. Prevent Mosquito breeding
• Manmade containers – Discarded tires,Flower
pots,oldoil drums,animal water troughs,water
storage vessels,plastic food containers
• Eliminated by
- Draining from coolers,tanks,barrels,drums & buckets
- Emptying coolers when not in use
- Cooperating with public health authorities

78. Role of Public health authorities
• National programme – Strengthened & Efficiently
implemented
• Legislations – Enforced
• Communities – Active cooperation

79. Epidemiological determinants
• Agent
- Group B Toga virus- KFD
virus
• Natural host & reservoir
- Rats, Squirrels, Birds &
Bats
- Monkeys- Amplifying host
- Cattle- Maintain tick
population
- Human- Incidental or
dead end host
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Vector
-Hard ticks
-Soft ticks
Host factors
-Age, Sex, Occupation,
Human activity
Transmission
- Monkey- Tick- Man
Incubation period
- 3 to 8 days

80. Clinical features
• Acute phase; 2 weeks
sudden fever,head ache & myalgia
• Second phase
meningoencephalitis,tremors, mental defects
• Severe cases
GI haemorrhages
DIAGNOSIS
Virus isolation from blood and serology.
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81. Control
• Ticks; carbaryl fenthion spray
2.24 kgs per hectare
• Hot spot- 50 metres around monkey death
• Restrict cattle movement in forests
• Vaccination; killed KFD vaccine
• Personal protection; repellants.
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82.  Be aware of peak mosquito hours
o For many mosquitoes, peak hours are between dusk
and dawn or evening and early morning.
o For the mosquitoes that transmits La Crosse
encephalitis virus peak hours are actually during the
daytime (dawn until dusk).
 Use insect repellant that contains DEET, picaridin,
IR3535 or oil of lemon eucalyptus on exposed skin
and clothing when outdoors.
o Always follow package directions.
o Apply sparingly to children, avoiding hands and face,
and wash them with soap and water when they
come indoors.
o Permethrin is a repellant that can be applied to
clothing and provide protection through multiple
washes. Do not apply permethrin-containing
repellants directly to skin.
 Wear protective clothing such as long sleeves,
pants, and socks when weather permits
 Install and repair window screens as needed to
keep mosquitoes out of homes
 Mosquitoes can lay eggs in small amounts of
water. Remove breeding sites around the
home:
o Empty standing water from flower pots, buckets,
barrels, and tires
o Change the water in pet dishes regularly
o Replace water in bird baths weekly
o Drill holes in tire swings so the water drains out
o Empty children’s wading pools and store on their
side when not in use
o Empty standing water from canoes and boats
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83. 85

84. 86

85. 87

86. Nat Vector Borne Disease Control Program
Objective of controlling malaria, kala azar, filaria, J.E,
dengue fever and dengue hemorrhagic fever.
Strategies for NVBDCP
1. Early diagnosis and prompt treatment
2. Integrated vector control
3. Epidemic preparedness and rapid response
4. Behavior change communication
5. Intersectoral coordination
6. Human resource development
7. Monitoring and evaluation.
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