Epidemiology of Communicable Disease

1. Kyasanur Forest Disease
MR. Vanindar Kumar B.C
Department of community health
nursing
GOVERNMENT COLLEGE OF NURSING,
FORT, BENGALURU

2. Introduction
• Kyasanur Forest Disease(KSD) was
recognized in 1957 in shimoga district of
karnataka state in south India. It is named after
the locality- kyasanur forest from where the virus
was isolated first.

3. Definition
– KFD is a febrile disease caused by an arbo virus
flavivirus and transmitted to man by the bite of
infective ticks, characterized by acute febrile
phase; gastrointestinal disturbance and hemorrhage
from nose, gums, stomach and intestine in severe
cases. It is followed by a second phase
characterized by mild meningoencephalitis in a
number of cases.

4. History …..
 Heavy mortality in two species of monkey
( Langur & Red faced bonnet ) in 1955 in forests of
Shimoga led to the discovery of KFD
 Mortality in monkeys was followed by acute febrile
prostrating illness among villagers and few human
deaths

5. History …….
Autopsy on monkeys
Place of reporting of First
monkey death in march 1957

6. Problem
• The disease is found in four district of
karnataka state in India covering an area
over 6000km. In 2004, 112 cases and 2
deaths were reported in karnataka due to
KF disease.

7. Kyasanur forest disease
 Found in India
 Limited originally to
Shimoga district in
Karnataka (800 sq km
 Newer foci in 3 more
districts namely
U.kannada,D. Kannada
and Chikmangaluru
( 6000 sq km )
 Serosurveys reveal KFD in
Kutch & Saurashthra

8. Problem statement
 The outbreak during 1983-1984 is the largest with
2167 cases and 69 deaths.
 In 1997 the cases came down to75 and deaths to 4.
 The number of human deaths varied between 4-15%
of the cases
 Even today few hundreds of cases and some deaths
are reported

9. Agent factors ..
 Kyasanur forest disease (KFD) is a febrile disease
associated with hemorrhages caused by an arbovirus
flavivirus.
 KFD virus is a member of group B togaviruses
 Belongs to Russian spring summer encephalitis
(RSSE) group of viruses
 Animal reservoirs :- squirrels and rats are the
main reservoirs

10. HOST FACTORS
 Age :majority between 20 and 40 years.
 Sex: males
 Occupation: Cultivators who visit forest with cattle or
cutting wood.
 Epidemic correlates with peak human activity in
forests i.e between January and June when
human activity is greatest in the forest.

11. Mode of transmission
• The transmission cycle involves mainly
monkey to monkey by the bite of infective
hard tick and from monkey to man.
• There is no evidence of man to man
transmission
• Incubation period:-
Between 3 to 8 days.

12. Clinical features
• 1. Acute Phase:-
• a. Sudden onset of fever, headache, severe
myalgia.
• b. In severe cases there is vomiting and
diarrhoea, epistaxis, gingival bleeding,
hematemesis, uterine bleeding among
women.
• 2. Secong phase:-
• symptoms of mild meningoenceohalitis; e.g.
severe headache, vomiting, neck regidity, and
mental disturbances.

13. Natural hosts & reservoirs
 Circulates in small mammals rats, squirrels, shrews
and bats are the main reservoirs .
 Neutralizing antibodies have also been found in
cattle, buffaloes, goats.
 Maintenance hosts – maintain the infection in nature

14. Environmental factors
 Tropical evergreen,
deciduous forests
 Clearing of forests for
cultivation and other
developmental activities
leads to change in tick
flaura and fauna and is
an important
determinant for
outbreaks

15. CLINICAL FEATURES
 Acute phase with sudden onset of fever, headache
,severe myalgia with prostation lasting for 2 weeks.
 GI disturbances and hemorrhagic manifestations in
severe cases
 Second phase characterized by mild
meningoencephalitis after an afebrile period of 7-21
days.
 Case fatality varies between 4-16%

16. Treatment
Conservative
 Antipyretics
 Analgesics
 Supportive therapy

17. Diagnosis
 Diagnosis by suspicion by clinical signs and
symptoms
 H/O occupation/travel in forests
 Detecting the presence of virus in blood.
 Serological evidence by haemagglutination and
immunofloresence

18. CONTROL
 Timely control decreases morbidity and mortality in
humans
CONTROL OF TICKS
 By aircraft mounted equipment to dispense lindane ,
carbaryl ,fenthion at 2.24 kg / hectare at forest floor
to kill the ticks.
 Spraying carried out within 50m around hot spots
 Restriction of cattle movement brings reduction in
vector population

19. CONTROL
Personal protection
 Adequate clothing
 Insect repellants such as DMP(Dimethyl
Phosphate), DEET (Diethyl-meta-toluamide)
provide 90-100% protection against tick bites
 Examine themselves for ticks and promptly remove
them
 Health education

20. CONTROL
Vaccination
with KFD vaccine of the population at risk. KFD vaccine
is a killed inactivated tissue culture vaccine.
2 doses each of 1ml with 4 weeks interval for adults and
0.5ml for children intramuscularly.

21. THANK YOU