1. 1

2. Vector borne diseases
DR RAHIM IQBAL
MBBS(Pb).MPH(H.S.A)
Senior Demonstrator
Rawalpindi Medical college
Rawalpindi
2

3. Vector borne 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
3

4. 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 4

5. 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
5

6. Vector born diseases
 Methods in which vectors are involved in
the transmission and propagation of
parasites.
 Mechanical transmission
 Propagative
 Cyclo-Propagative
 Cyclo-developmental
 Biological transmission
6

7. Malaria
7

8. MALARIA
Malaria is a protozoal disease caused by
infection with parasites of the genus
PLASMODIUM and transmitted to man
by certain species of infected female
Anopheline mosquito. 8

9. HISTORY
 Malaria is one of the oldest recorded
disease in the world.
 1880; Laveran a French Army Surgeon
discovered the malaria parasite in
Algiers, North Africa.
 1897; Ronald Ross, who discovered the
transmission of malaria by Anopheline
mosquitoes. 9

10. TYPES OF MALARIA
1. Tribal Malaria:
2. Rural Malaria:
3. Urban Malaria:
4. Malaria in Project Areas:
5. Border Malaria:
10

11. AGENT FACTORS
a). AGENT:
“Malaria in man is caused by four
distinct species of the malaria Parasite:”
* P. Vivax,
* P. Falciparum
* P. Malariae
* P. Ovale.
11

12. LIFE HISTORY:
i). Asexual Cycle:
* Hepatic Phase
* Erythrocytic Phase
ii). Sexual Cycle:
12

13. Malaria
b). RESERVOIR OF INFECTION:
c). PERIOD OF COMMUNICABILITY:
13

14. HOST FACTORS
 Age • Housing
 Sex • Population Mobility
 Race • Occupation
 Pregnancy • Human Habit
 Socioeconomic • Immunity
Development 14

15. MODE OF TRANSMISSION
a) Vector Transmission
b) Direct Transmission
c) Congenital Malaria
15

16. INCUBATION PERIOD
This is the length of time between the infective
mosquito bite and the first appearance of clinical
signs of which fever is most common. This period
is usually not less than 10 days.
Extrinsic incubation period=organism is present
in the vector+excrete to infect ie eligible to infect16

17. CLINICAL FEATURES
a) Cold Stage
b) Hot Stage
c) Sweating Stage
17

18. DIAGNOSIS (malaria)
18

19. MEASUREMENT OF MALARIA
PRE-ERADICATION ERA:
In the pre-eradication era, the magnitude of
the malaria problem in a country used to be
determined mostly from the reports of the
clinically diagnosed malaria cases.
The classical malariometric measures are
spleen rate, average enlarged spleen,
parasite rate etc. in a control programe, the
case detection machinery is weak. Therefore,
the classical malariometric measure may
provide the needed information, i.e. the
trend of the disease.
19
Continued:

20. a). SPLEEN RATE:
It is defined as the percentage of children
between 2 & 10 yrs of age showing
enlargements of spleen. Adults are excluded
from spleen surveys because causes other
than malaria frequently operate in causing
splenic enlargement in them. The spleen
rate is widely used for measuring the
endemicity of malaria in a community. 20
Continued:

21. b). AVERAGE ENLARGED SPLEEN:
This is a further refinement of spleen rate,
denoting the average size of the enlarged
spleen. It is useful malariometric index.
c). PARASITE RATE:
It is defined as the percentage of children
between the ages 2 & 10yrs showing
malaria parasites in their blood films.
21
Continued:

22. d). PARASITE DENSITY INDEX:
It indicates the average degree of
parsitaemia in a sample of well defined
group of the population. Only the
positive slides are included in the
denominator. 22
Continued:

23. e). INFANT PARASITES:
It is defined as the percentage of infants below
the age of one year showing malaria parasites in
their blood film. It is regarded as the most
sensitive index of recent transmission of malaria
in a locality. If the infant parasite rate is zero for 3
consecutive years in a locality, it is regarded as
absence of malaria transmission even though, the
Anopheline vectors responsible for previous
transmission may remain.
23

24. f). PROPORTIONAL CASE RATE:
Since the morbidity rate is difficult to determine,
except in conditions when the diagnosis and
reporting to each case is carried to perfection,
proportional case rate is used.
It is defined as the number of cases diagnosed as
clinical malaria for every 100 patients attending
the hospitals and dispensaries. This is a crude
index because the cases are not related to their
time/space distribution.
24

25. Important parameters
 Annual parasites incidence(API)
 API=confirm cases during year/population under
surveillance*1000
 Annual blood examination
rate(ABER)/population
 Number of slides examined*100
 Annual falciparum incidence(API)
 Slide positivity rate(SPR)
 Slide falciparum rate(SFR)
25

26. MODIFIED PLAN OF OPERATION
1. Objectives
2. Reclassification of endemic areas
3. Areas with API > 2:
a). Spraying
b). Entomological Assessment
c). Surveillance
d). Treatment of cases
26
Continued:

27. 4. Areas with API < 2:
a). Spraying
b). Surveillance
c). Treatment
d). Follow Up
e). Epidemiological investigation
5. Drug distribution centers & fever
treatment depots
6. Urban malaria scheme
7. P. Falciparum containment
8. Research
9. Health education 27

28. SURVEILLANCE
a) Active Surveillance
b) Passive Surveillance
c) Parameters of malaria surveillance
28

29. APPROACHES & STRATEGIES OF
MALARIA CONTROL
a. Management of malaria cases
b. Disease control strategies
i). Case Detection
ii). Treatment
* Presumptive treatment
*Radical Treatment
29

30. per tablet or
Generic Name Common For prophylaxis For treatment
capsule
trade names
Chloroquineb Aralen 100 / 150mg 300mg (base) = tablets 600 mg (base) on
Avlochlor (base) of 100mg or 2 tablets of the 1st & 2nd days,
150mg once a week 300mg (base) on
Nivaquine
OR the third day
Resochin (total 10 tablets of
100mg (base) = 1 tablet
150mg or 15 of
of 100mg daily for six
days per week 100mg.
Proguanil Paludrine 100 mg 200mg = 2 tablets once Not applicable
a day
Sulfadoxine- Fansidar 500mg + 25mg Not applicable 1500mg + 75mg
pyrimethamine = 3tablets in one
dose
Sulfalene- Metakelfin 500mg + 25mg Not applicable 1500mg + 75mg
pyrimethamine = 3tablets in one
dose
30

31. Mefloquine Lariam 250 mg 250mg = 1 1000mg (4tablets) or
Mephaquin tablet one a 15mg/kg of body
week, on the weight, whichever is
same day each lower in one dose
week OR
100mg (4tablets)
initially, followed by
500mg (2tablets) 6-
8hrs later.
Quinine 300mg Not applicable 600mg (2tablet) 3
times a day for 7 days
(total 42 tablets)
Doxycycline Vibramycin 100mg 100mg = 1 Not applicable
capsule once a
day
Halofantrineb.f Halfan 250mg Not applicable 500mg (2tablets) in
one dose + 500mg
after 6hrs, + 500mg
after 6 more hrs, (total
31
6 tablets in 12hrs)

32. Drugs resistance malaria
 WHO recommendation.
32

33. Situation of Clinical Malaria (Fever) in
INTRODUCTION Pakistan
Malaria is one of the most devastating tropical disease in the
world, with nearly 2.1 billion people at risk of infection. It is
particularly dangerous for young children and for pregnant women
and their unborn children, although others may be seriously
affected in some circumstances. About 250 to 300 million cases of
malaria occur annually many among young children. New anti-
malarial drugs and more efficient diagnostic techniques are being
tested to cope with the problem. Malaria is a curable and
preventable disease, but it still kills many people. The main
reasons for this unsatisfactory situation are:
 Some people do not come for treatment until they are very ill
because:
• they do not realize they might have malaria (people often
think they have a cold, influenza or other common infection);
• they do not realize that malaria is very dangerous; or
• they live far away from health care facilities.
 People living far from health services will often go to local
medicine vendors (sellers) for advice, which is not always
appropriate, or to buy medicines, which are not always effective.
33
 Many people do not know what causes malaria or how it is spread,
so they are not able to protect themselves from the disease.

34.  Pakistan launched Malaria eradication campaign with the
help of WHO in 1960. But eradication of malaria could not
be achieved because of socio- economic and
epidemiological factors and so it poses a potential threat to
the health of millions of people. On the advice of WHO,
Malaria Eradication Programme was converted into Malaria
Control Programme. The current project is an extension of
on- going Malaria Control Programme.
A patient of any age having axillary or oral temperature of
38?C or more, rectal temperature of 38.5?C or more,
continues or irregular at the start of the illness, but soon it
may become irregular with attacks every 2-3 days. The
attack begins with sever shivering, followed by fever and
finally by profuse sweating.
Malaria is a disease that is caused by the presence of very
small organisms (malaria parasites) in the blood. Malaria
parasites are so small that they can only be seen under a 34
microscope. They feed on the blood cells, multiply inside

35.  NHMIS is actively functioning in almost all the districts of
the country. Presently National HMIS is collecting valuable
information, which flows directly from the peripheral health
facilities to the District Computer Centers, then to the
Divisional and the Provincial Computer Centers. Ultimately,
the information reaches the National HMIS Cell on
computer diskettes where it is analyzed through HMIS
software and also through Statistical Package of Social
Sciences (SPSS).
This monograph has been compiled from the data received
by the National HMIS Cell of the Ministry of Health from
the HMIS Cells located within the provincial health
departments. The National HMIS Cell has made all efforts
in compiling this bulletin to reflect the true picture of
malaria burden in Pakistan to its readers.
The prime purpose of this monograph is to present the
analysis of malaria data received from the provinces during
Jan 1998 - July 2000. This report is hoped to generate
interest and debate at various levels of health care delivery
system as to pinpoint areas with high endemicity of 35
malaria, particularly the falciprum malaria prevalence in

36. Malaria Vaccine
burning issue of today
1)sexual blood stage vaccine
2)second vaccine is designed to arrest the
development of the parasite in the mosquito
3)SP166(cocktail) vaccine for p.falciparum(dr
.m.Pattaryo)
4)Transmission blocking vaccine.Pfs 25(USA 1995)
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37. Thank you
Very much
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