1. Vector-borne diseases are transmitted by arthropods like mosquitoes, flies, ticks, and mites or other living carriers like snails. Common vector-borne diseases include malaria, dengue, yellow fever, and lymphatic filariasis. 2. Lymphatic filariasis is caused by infection with nematode worms transmitted via mosquito bites. It causes swelling in the limbs and genitals. 3. Leishmaniasis is caused by protozoa of the genus Leishmania transmitted by the bite of infected sand flies. It includes visceral leishmaniasis and cutaneous forms. 4. Scabies is caused by the mite S

1. Vector born diseases
DR RAHIM IQBAL
MBBS(Pb).MPH(H.S.A)
Senior Demonstrator
Rawalpindi Medical college
Rawalpindi
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2. Vector born diseases
Vector
It is defined as an arthropod or any living
carrier (e.g. snail) that transport an
infectious agent to a susceptible
individuals. The transmission by a vector
may mechanical or biological
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3. Arthropods-borne diseases
Arthropods Diseases transmitted
Mosquito Malaria, Filariasis, Dengue, Yellow Fever
Housefly Typhoid, Diarrhea, Gastro-enteritis
Amoebiasis, Poliomyelitis, Trachoma
Sand fly Kalaazar, Sand fly fever, Oraya Fever
Tsetse fly Sleeping Sickness
Louse Epidemic Typhus, Relapsing fever
Rat Flea Plague, endemic typhus
Black Fly Onchocerciasis 3

4. Arthropods-borne diseases
Hard tick Viral Hemorrhagic fever, Tick Paralysis , Viral
Encephalitis
Soft Tick Q fever, Relapsing Fever
Itch Mite Scabies
Cyclops Guinea-worm disease, Fish tape worm
Cockroach Enteric pathogens
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5. LYMPHATIC
FILARISIS
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6. LYMPHATIC FILARIASIS
The term “LYMPHATIC FILARIASIS” covers
infection with three closely related nematode
worms – W. bancrofti, B. malayi and B. timori. All
three infections are transmitted to man by the
bites of infective mosquitoes. All three parasites
have basically similar life cycles in man.
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7. HUMAN FILARIAL
INFECTIONS
ORGANISM VECTORS DISEASE
PRODUCED
Wuchereia bancrofti Culex Mosquitoes Lymphatic filariasis
Brugia malaya Mansonia -”- -”- -”-
Brugia timori Anopheles -”- -”- -”-
Mansonia -”-
Onchocera volvulus Simultum flies Subcutaneous nodules;
River blindness
Loa loa Chrysops flies Recurrent, transient
subcutaneous swellings
T. Perstans Culicoides Probably rarely any clinical
illness
T. Streptocerca -”- -”- -”-
Mansonella ozzardi -”- 7 -”- -”-

8. AGENT FACTORS
a) Periodicity
b) Life Cycle
c) Reservoir of infection
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9. HOST FACTORS
a) Age
b) Sex
c) Migration
d) Immunity
e) Social Factors
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10. ENVIRONMENTAL FACTORS
a) Climate
b) Drainage
c) Town Planning
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11. VECTORS OF LYMPHATIC FILARIASIS
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12. MODE OF TRANSMISSION
Filariasis is transmitted by the bite of infected
vector mosquitoes. The parasite is deposited
near the site of puncture. It passes through the
punctured skin or may penetrate the skin on its
own and finally reach the lymphatic system. The
dynamics of transmission depends upon the
man mosquito contact (e.g. infective biting rate).
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13. 1). Incubation period
8 to 16 months
2). Clinical manifestations
a) lymphatic filariasis
b)occult filariasis
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14. 1. LYMPHATIC FILARIASIS:
a). Asymptomatic microfilaraemia
b). Asymptomatic microfilaraemia
c). Stage of acute manifestations
d). Stage of chronic obstructive lesions
2. OCCULT FILARIASIS:
The tem occult or cryptic filariasis refers to
filarial infections in which the classical clinical
manifestations are not present and Mf are not
found in the blood.
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15. FILARIA SURVEY
The size of the sample to be examined I a
filaria survey varies with the type of survey,
whether it is a routine survey or survey for
evaluation.
1. Mass Blood Survey
* The thick film
* Membrane filter concentration method
* DEC provocation test
2. Clinical Survey
3. Xenodiagnosis
4. Entomological Survey
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16. ASSESSMENT OF FILARIA
CONTROL PROGRAMMES
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17. 1. Clinical Parameters
2. Parasitological -”-
a). Microfilaria Rate
b). Filarial Endemicity Rate
c). Microfilarial Density
d). Average Infestation Rate
3. Entomological Parameters
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18. Control measures
• CHEMOTHERAPY:
a). Diethylcarbamazine
b). Filaria control in the community
(i). Mass Therapy
(ii). Selective treatment
(iii). DEC medicated salt
(iv). Ivermectin
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19. 1. VECTOR CONTROL:
a). Antilarval measures
(i). Chemical control
(ii). Removal of Pistia Plant
(iii). Minor environmental measures
b). Anti-adult measures
c). Personal Prophylaxis
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20. LEISHMANIASIS
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21. LEISHMANIASIS
“Leishmaniasis are a group of protozoal diseases caused by parasites of the
genus Leishmnania, and transmitted to man by the bite of female
phlebotomine sandfly.” they are responsible for various syndromes in
human beings
1. kalaazar or visceral leishmaniasis (VL)
2. cutaneous leishmaniasis (CL)
3. mucocutaneous leishmaniasis (MCL)
4. anthroponotic cutaneous leishmaniasis (ACL)
5. zoonotic cutaneous leishmaniasis (ZCL)
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22. AGENT FACTORS:
a). Agents
b). Reservoirs of infection
HOST FACTORS:
a). Age
b). Sex
c). Population Movement
d). Socio-economic status
e). Occupation
f). Immunity 22

23. ENVIRONMENTAL FACTORS:
a). Altitude
b). Season
c). Rural Areas
d). Vectors
e). Development projects
MODE OF TRANSMISSION:
From man to man by the bite of female phlebotomine
sandfly or P. argentipes
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24. INCUBATION PERIOD
1to 4 months range is 10 days to 2 years
Clinical Features:
1). Kala Azar (VL)
2). Cutaneous Leishmaniasis
3). Mucocutaneous Leishmaniasis
Laboratory diagnosis:
1). Parasitological diagnosis
2). Aldehyde test
3). Serological tests
4). Leishmanin (Montenegro) test
5). Haematological findings
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25. CONTROL MEASURES
1 Control of reservoir:
* Treatment
* Animal reservoirs
2. Sandfly control
3. Personal prophylaxis
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26. SCABIES
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27. SCABIES
• Discovered – 1687
• Sarcoptes Scabiei / Acarus Scabiei – very small
• The female parasite burrows into the epidermis
where it breeds and causes the condition known
as scabies / itch.
• Species of germs – infest animals like dogs, cattle
& horse.
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29. DIAGNOSIS OF SCABIES
The main diagnostic features of scabies are:
a). The patient complains of itching which is worse
at night.
b). Examination reveals follicular lesions at the
affected site
c). Secondary infection leads to crusted papules
and pustules
d). The diagnosis is probable if the other members
of the household are affected
e). Confirmation of the diagnosis may be made by
searching for the parasite in the skin debris under
microscope.
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30. Treatment of scabies
1. Benzyl Benzoate
2. HCH
3. Tetmosol
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31. GENERAL VIEW
Nam Causative Ho Reservo Mode of
e of Agent st ir Transmission
Dise
ase
Sarcoptes Man •Man 1. Direct Transmission
Scabi Scabiei or •Sometime Direct close free
es Acarus Scabiei s Domestic contact with infected
(Itch Mite) Animals person. Via
a). Hand shaking
b). Embracing
c). Sleeping together
etc.
1. Indirect
Transmission
It is via using non
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living things

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