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Vector born diseasesVector born diseases

DR RAHIM IQBALDR RAHIM IQBALMBBS(Pb).MPH(H.S.A) MBBS(Pb).MPH(H.S.A) Senior DemonstratorSenior Demonstrator

Rawalpindi Medical college Rawalpindi Medical college RawalpindiRawalpindi

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Vector born diseasesVector born diseases

VectorVectorIt is defined as an arthropod or any It is defined as an arthropod or any

living carrier (e.g. snail) that living carrier (e.g. snail) that transport an infectious agent to a transport an infectious agent to a

susceptible individuals. The susceptible individuals. The transmission by a vector may transmission by a vector may

mechanical or biologicalmechanical or biological

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Arthropods-borne diseasesArthropods-borne diseases

ArthropodsArthropods Diseases transmittedDiseases transmitted

MosquitoMosquito Malaria, Filariasis, Dengue, Yellow FeverMalaria, Filariasis, Dengue, Yellow Fever

HouseflyHousefly Typhoid, Diarrhea, Gastro-enteritis Typhoid, Diarrhea, Gastro-enteritis

Amoebiasis, Poliomyelitis, TrachomaAmoebiasis, Poliomyelitis, Trachoma

Sand flySand fly Kalaazar, Sand fly fever, Oraya Fever Kalaazar, Sand fly fever, Oraya Fever

Tsetse flyTsetse fly Sleeping Sickness Sleeping Sickness

LouseLouse Epidemic Typhus, Relapsing fever Epidemic Typhus, Relapsing fever

Rat FleaRat Flea Plague, endemic typhusPlague, endemic typhus

Black FlyBlack Fly Onchocerciasis Onchocerciasis

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Arthropods-borne diseasesArthropods-borne diseases

Hard tickHard tick Viral Hemorrhagic fever, Tick Paralysis , Viral Hemorrhagic fever, Tick Paralysis , Viral Encephalitis Viral Encephalitis

Soft Tick Soft Tick Q fever, Relapsing Fever Q fever, Relapsing Fever

Itch MiteItch Mite Scabies Scabies

Cyclops Cyclops Guinea-worm disease, Fish tape wormGuinea-worm disease, Fish tape worm

Cockroach Cockroach Enteric pathogensEnteric pathogens

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LYMPHATIC LYMPHATIC FILARISISFILARISIS

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LYMPHATIC FILARIASISLYMPHATIC FILARIASIS

The term The term “LYMPHATIC FILARIASIS” “LYMPHATIC FILARIASIS” covers covers

infection with three closely related nematode infection with three closely related nematode

worms – worms – W. bancrofti, B. malayi and B. timori.W. bancrofti, B. malayi and B. timori.

All three infections are transmitted to man by All three infections are transmitted to man by

the bites of infective mosquitoes. All three the bites of infective mosquitoes. All three

parasites have basically similar life cycles in parasites have basically similar life cycles in

man.man.

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HUMAN FILARIAL HUMAN FILARIAL INFECTIONSINFECTIONSORGANISMORGANISM VECTORSVECTORS DISEASE DISEASE

PRODUCEDPRODUCEDWuchereia bancroftiWuchereia bancrofti Culex MosquitoesCulex Mosquitoes Lymphatic filariasisLymphatic filariasis

Brugia malayaBrugia malaya Mansonia -”-Mansonia -”- -”- -”--”- -”-

Brugia timoriBrugia timori Anopheles -”-Anopheles -”-

Mansonia -”-Mansonia -”--”- -”--”- -”-

Onchocera volvulusOnchocera volvulus Simultum fliesSimultum flies Subcutaneous nodules; Subcutaneous nodules; River blindnessRiver blindness

Loa loaLoa loa Chrysops fliesChrysops flies Recurrent, transient Recurrent, transient subcutaneous swellingssubcutaneous swellings

T. PerstansT. Perstans CulicoidesCulicoides Probably rarely any Probably rarely any clinical illnessclinical illness

T. StreptocercaT. Streptocerca -”--”- -”- -”--”- -”-

Mansonella ozzardiMansonella ozzardi -”--”- -”- -”--”- -”-

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a)a)PeriodicityPeriodicity

b)b)Life CycleLife Cycle

c)c) Reservoir of infectionReservoir of infection

AGENT FACTORSAGENT FACTORS

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HOST FACTORSHOST FACTORS

a)a)AgeAge

b)b)SexSex

c)c) MigrationMigration

d)d) ImmunityImmunity

e)e)Social FactorsSocial Factors

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ENVIRONMENTAL FACTORSENVIRONMENTAL FACTORS

a)a)ClimateClimate

b)b)DrainageDrainage

c)c) Town PlanningTown Planning

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VECTORS OF LYMPHATIC FILARIASISVECTORS OF LYMPHATIC FILARIASIS

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MODE OF TRANSMISSIONMODE OF TRANSMISSIONFilariasis is transmitted by the bite of Filariasis is transmitted by the bite of

infected vector mosquitoes. The parasite is infected vector mosquitoes. The parasite is

deposited near the site of puncture. It deposited near the site of puncture. It

passes through the punctured skin or may passes through the punctured skin or may

penetrate the skin on its own and finally penetrate the skin on its own and finally

reach the lymphatic system. The dynamics reach the lymphatic system. The dynamics

of transmission depends upon the man of transmission depends upon the man

mosquito contact (e.g. infective biting rate).mosquito contact (e.g. infective biting rate).

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1). Incubation period1). Incubation period 8 to 16 months8 to 16 months

2). Clinical 2). Clinical manifestationsmanifestations

a) lymphatic filariasis a) lymphatic filariasis

b)occult filariasis b)occult filariasis

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1.1. LYMPHATIC FILARIASIS:LYMPHATIC FILARIASIS:

a). Asymptomatic microfilaraemiaa). Asymptomatic microfilaraemia

b). Asymptomatic microfilaraemiab). Asymptomatic microfilaraemia

c). Stage of acute manifestationsc). Stage of acute manifestations

d). Stage of chronic obstructive d). Stage of chronic obstructive

lesionslesions

2.2. OCCULT FILARIASIS:OCCULT FILARIASIS:

The tem occult or cryptic filariasis refers to The tem occult or cryptic filariasis refers to

filarial infections in which the classical filarial infections in which the classical

clinical manifestations are not present and clinical manifestations are not present and

Mf are not found in the blood. Mf are not found in the blood.

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FILARIA SURVEYFILARIA SURVEY

The size of the sample to be examined I a The size of the sample to be examined I a

filaria survey varies with the type of survey, filaria survey varies with the type of survey,

whether it is a routine survey or survey for whether it is a routine survey or survey for

evaluation.evaluation.

1.1. Mass Blood SurveyMass Blood Survey

* The thick film* The thick film

* Membrane filter concentration * Membrane filter concentration

methodmethod

* DEC provocation test* DEC provocation test

2.2. Clinical SurveyClinical Survey

3.3. XenodiagnosisXenodiagnosis

4.4. Entomological SurveyEntomological Survey

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ASSESSMENT OF FILARIA ASSESSMENT OF FILARIA

CONTROL PROGRAMMESCONTROL PROGRAMMES

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1.1. Clinical ParametersClinical Parameters

2.2. Parasitological -”-Parasitological -”-

a). Microfilaria Ratea). Microfilaria Rate

b). Filarial Endemicity Rateb). Filarial Endemicity Rate

c). Microfilarial Density c). Microfilarial Density

d). Average Infestation Rated). Average Infestation Rate

3.3. Entomological ParametersEntomological Parameters

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Control measuresControl measures

• CHEMOTHERAPY:CHEMOTHERAPY:

a). Diethylcarbamazinea). Diethylcarbamazine

b). Filaria control in the communityb). Filaria control in the community

(i). Mass Therapy(i). Mass Therapy

(ii). Selective treatment(ii). Selective treatment

(iii). DEC medicated salt(iii). DEC medicated salt

(iv). Ivermectin(iv). Ivermectin

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1.1. VECTOR CONTROL:VECTOR CONTROL:

a). Antilarval measuresa). Antilarval measures

(i). Chemical control(i). Chemical control

(ii). Removal of Pistia Plant(ii). Removal of Pistia Plant

(iii). Minor environmental (iii). Minor environmental

measuresmeasures

b). Anti-adult measuresb). Anti-adult measures

c). Personal Prophylaxisc). Personal Prophylaxis

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LEISHMANIASISLEISHMANIASIS

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LEISHMANIASISLEISHMANIASIS““Leishmaniasis are a group of protozoal diseases caused by parasites of the genus Leishmaniasis are a group of protozoal diseases caused by parasites of the genus Leishmnania,Leishmnania, and transmitted to and transmitted to

man by the bite of man by the bite of female phlebotomine sandfly.” female phlebotomine sandfly.” they are responsible for various syndromes in human beingsthey are responsible for various syndromes in human beings

1. kalaazar or visceral leishmaniasis (VL)1. kalaazar or visceral leishmaniasis (VL)

2. cutaneous leishmaniasis (CL)2. cutaneous leishmaniasis (CL)

3. mucocutaneous leishmaniasis (MCL)3. mucocutaneous leishmaniasis (MCL)

4. anthroponotic cutaneous leishmaniasis (ACL)4. anthroponotic cutaneous leishmaniasis (ACL)

5. zoonotic cutaneous leishmaniasis (ZCL)5. zoonotic cutaneous leishmaniasis (ZCL)

6. POST KALA AZAR DERMAL LEISHMANIASIS (PKDL) 6. POST KALA AZAR DERMAL LEISHMANIASIS (PKDL)

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AGENT FACTORS:AGENT FACTORS:

a). Agentsa). Agents

b). Reservoirs of infectionb). Reservoirs of infection

HOST FACTORS:HOST FACTORS:

a). Agea). Age

b). Sexb). Sex

c). Population Movementc). Population Movement

d). Socio-economic statusd). Socio-economic status

e). Occupatione). Occupation

f). Immunityf). Immunity

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ENVIRONMENTAL FACTORS:ENVIRONMENTAL FACTORS:

a). Altitudea). Altitude

b). Seasonb). Season

c). Rural Areasc). Rural Areas

d). Vectorsd). Vectors

e). Development projectse). Development projects

MODE OF TRANSMISSION:MODE OF TRANSMISSION:

From man to man by the bite of female phlebotomineFrom man to man by the bite of female phlebotomine

sandfly or P. argentipessandfly or P. argentipes

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INCUBATION PERIODINCUBATION PERIOD1to 4 months range is 10 days to 2 years1to 4 months range is 10 days to 2 years

Clinical Features:Clinical Features:

1). Kala Azar (VL)1). Kala Azar (VL)

2). Cutaneous Leishmaniasis2). Cutaneous Leishmaniasis

3). Mucocutaneous Leishmaniasis3). Mucocutaneous Leishmaniasis

Laboratory diagnosis:Laboratory diagnosis:

1). Parasitological diagnosis1). Parasitological diagnosis

2). Aldehyde test2). Aldehyde test

3). Serological tests3). Serological tests

4). Leishmanin (Montenegro) test4). Leishmanin (Montenegro) test

5). Haematological findings5). Haematological findings

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CONTROL MEASURESCONTROL MEASURES

1 1 Control of reservoir: Control of reservoir:

* Treatment* Treatment

* Animal reservoirs* Animal reservoirs

2.2. Sandfly controlSandfly control

3.3. Personal prophylaxisPersonal prophylaxis

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SCABIESSCABIES

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SCABIESSCABIES

• Discovered – 1687Discovered – 1687

• Sarcoptes Scabiei / Acarus Scabiei – very small Sarcoptes Scabiei / Acarus Scabiei – very small

• The female parasite burrows into the The female parasite burrows into the

epidermis where it breeds and causes the epidermis where it breeds and causes the

condition known as scabies / itch.condition known as scabies / itch.

• Species of germs – infest animals like dogs, Species of germs – infest animals like dogs,

cattle & horse.cattle & horse.

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DIAGNOSIS OF SCABIESDIAGNOSIS OF SCABIESThe main diagnostic features of scabies The main diagnostic features of scabies

are:are:a). a). The patient complains of itching which is The patient complains of itching which is

worse at night.worse at night.b). Examination reveals follicular lesions at the b). Examination reveals follicular lesions at the

affected siteaffected sitec). Secondary infection leads to crusted papules c). Secondary infection leads to crusted papules

and pustulesand pustulesd). The diagnosis is probable if the other d). The diagnosis is probable if the other

members of the household are affectedmembers of the household are affectede). Confirmation of the diagnosis may be made e). Confirmation of the diagnosis may be made

by searching for the parasite in the skin debris by searching for the parasite in the skin debris under microscope.under microscope.

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Treatment of scabiesTreatment of scabies

1.1. Benzyl BenzoateBenzyl Benzoate

2.2. HCHHCH

3.3. TetmosolTetmosol

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GENERAL VIEWGENERAL VIEWNamName of e of DiseDiseasease

Causative Causative AgentAgent

HoHostst

ReservReservoiroir

Mode of Mode of TransmissionTransmission

ScabiScabieses

Sarcoptes Sarcoptes Scabiei or Scabiei or Acarus Scabiei Acarus Scabiei (Itch Mite)(Itch Mite)

ManMan •ManMan

•SometimSometimes es Domestic Domestic AnimalsAnimals

1.1.Direct Direct TransmissionTransmission

Direct close free Direct close free contact with contact with infected person. Viainfected person. Via

a). Hand shakinga). Hand shaking

b). Embracingb). Embracing

c). Sleeping together c). Sleeping together etc.etc.

1.1.Indirect Indirect TransmissionTransmission

It is via using non It is via using non living thingsliving things

a). Clothesa). Clothes

b). Towel etc. also b). Towel etc. also called Fomite Bornecalled Fomite Borne

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