EPIDEMIOLOGICAL TRIAD VED (1).pptx

E
P
I
D
E
M
I
O
L
O
G
I
C
A
LT
R
I
A
D
&
M
U
L
T
I
F
A
C
T
O
R
I
A
LC
A
U
S
A
T
I
O
N
V
E
D
V
R
A
TP
A
L
I
W
A
L(
9
5
)
M
B
B
S2
0
2
1
-
2
2
A
S
M
C
,
E
T
A
H

I
N
T
R
O
D
U
C
T
I
O
N
Forlongtimem
a
nwasgroupingindarknessa
b
o
u
tthe
causationofdiseases,
Severaltheoryofdiseasesweread
v
an
c
edfromtimeto
timetoExplaindiseasecausationsuchas:-
Supernaturaltheory
T
h
eo
r
yofh
u
m
o
r
sbyGreekan
dI
n
d
ian
s
T
h
e
o
r
yofcontagion
T
h
emiasmatictheory
T
h
eo
r
yofs
p
o
n
t
an
eousgenerationetc
K. Park’s textbook of preventive and social
medicine 25th edition

GermT
h
e
o
r
yofDisease
T
h
e breakthrough came in 1
8
6
0
,
w
h
e
nFrench bacteriologist Louis
Pasteur demon
st
r
ated the presence of bacteria in air. I
n1
8
7
3h
e
a
d
v
a
n
c
e
dtheoryofS
p
o
n
t
a
n
e
o
u
sgeneration..
Later R
o
ber
t K
o
ch discovered anthrax caused by bacteria a
n
d
G
O
L
D
E
NERA of Bacteriology b
e
g
u
n with discovery of mi
crobe
aftermicrobe..
G
o
n
n
o
c
o
c
u
sin1
8
7
9
T
y
p
h
o
i
dbacillus,Pneumococciin1
8
8
0
Tuberclebacillusin1
8
8
2
Cholerain1
8
8
3
Diptheriain1
8
8
4andsoo
n
…
Louis Pasteur
K. Park’s textbook of preventive and
social

Allattentionw
asfocusedonmicrobesa
n
dtheirrolein
diseasecausation,an
ddiseasem
o
d
e
laccordinglyis:-
• D
I
SE
A
SEA
G
E
N
T M
A
N D
I
SE
A
SE
•
• I
n1
8
7
8R
o
ber
tK
o
chsu
mmar
i
z
edhis
experimentsontheetiologyofw
o
u
n
d
infection,B
yinoculatinganimalswith
materialfromvarioussources,h
e
producedsixtypesofinfection,each
causedbyaspecificmicroorganism.
• H
ethentransferredtheseinfectionsby
• inoculationthroughseveralkindsof
animals,reproducingtheoriginalsix
ty
p
es.
Robert Koch
social

I
nthats
t
u
d
y
,heobserveddifferencesinpathogenicityfor
differentspeciesofhostsan
ddemo
ns
t
rat
edthatthe
animalb
o
d
yis anexcellentapparatusforthecultivationof
bacteria.
social
ThesetheoriesofPasteura
n
dK
o
c
hconfirmedthegerm
theoriesofdisease.
Later,RobertK
o
c
hhasgivenK
o
c
hPostulates

Aspecificmicroorganismisalwaysassociatedwith
agivendisease.
T
h
emicroorganismcanbeisolatedfromthediseased
animala
n
dg
r
o
w
ninpurecultureinthelaboratory.
T
h
eculturedmicrobewillcausediseasew
h
e
n
transferredtoahealthyanimal.
T
h
es
a
m
etypeofmicroorganismcanbeisolatedfrom
then
e
w
l
yinfectedanimal.
social
Koch’spostulates,are:

T
h
eG
e
r
mtheoryhasm
a
n
ylimitation,I
tw
as
unabletoexplain
W
h
yonlys
o
m
epeoplesufferfromthediseaseafter
exposure to microorganism and not all,as with
exposuretotuberclebacilli.
W
h
y
s
o
m
epeopledonotsufferfromthedisease
eventhroughtheyharborthep
a
t
h
o
g
e
nintheb
o
d
y
.As
incarrierstate
This lead to d
e
m
a
n
d of a broader concept of
disease causation that synthesized the basic
factorsofA
g
e
n
t
,H
o
s
tan
dE
n
v
ir
on
ment.
social

T
h
elimitationofgermtheoryledtotheconceptof
“EpidemiologicalorEcologicalT
r
i
a
d
”
.
AccordingtothetheoryofEpidemiologicaltriadeveryone
ex
p
o
s
e
dtodiseaseag
en
tdidnotcontractthedisease,
Thism
e
a
n
sitisnotonlythecausativeag
en
tthatis
responsiblefordisease.
ButthereareanotherFactorsalsorelatedtoM
a
nan
d
E
n
v
i
r
o
n
m
e
n
tw
hichcontributestodisease.
social

AGENT
social
HOST
ENVIORNMENT

AGENT
social
BIOLOGICAL
MECHANICHAL
NUTRITIONAL
PHYSICAL/CHEMICAL

HOST
social
GENETIC
MAKEUP
AGE/SEX
LITERACY
INCOME
LIFE
STYLE
IMMUNITY

ENVIRONMENT
social
PHYSICAL
BIOLOGICAL
PSYCHOLOGICAL
CUSTOMS

Accordingtothism
o
d
e
lofEpidemiologicaltriad
diseaseoccursw
h
e
ntheequilibriumb
e
t
w
e
e
nagent,
hosta
n
de
n
v
i
r
o
n
men
tisdisturbed.
social
Thism
o
d
e
lexplainsthats
o
m
epersonsdonotsuffer
fromthediseaseeventhroughtheyharborthe
p
at
h
o
g
e
n
sbecauseanequilibriumisestablished
b
e
t
w
e
e
nthecausativeag
en
tan
dthehost.

Epidemiologicaltriadtheoryisnotapplicableforn
o
n
infectiousa
n
dchronicdiseaseslikeCoronaryartery
diseaes,Mentalillnessetc,becausethesediseasehas
m
a
n
ycausesa
n
dmultiplefactors.
ThisledustothinkfortheMultipleFactorsbehind
adiseasecausation.
social

M
U
L
T
I
F
A
C
T
O
R
I
A
LC
A
U
S
A
T
I
O
N
social

T
h
etheoryofMultifactorialCausationofDiseasewas
firstproposedbyGalenin1
3
0
-
1
5
0A
D
I
n1
8
1
9
-
1
9
0
1
,thistheorywasagainp
u
tforwardb
y
PetenKoferofG
e
r
m
a
n
y
,butthiswaso
v
e
r
s
h
a
d
o
w
e
db
y
germtheoryatthattime.
Galensaidthefactorsare:-
 Predisposing
 Exciting a
n
d
 Environmental
social
MultifactorialCausationofDisease

T
H
E
S
EP
R
E
D
I
S
P
O
S
I
N
GFACTO
R
SAR
E
:
-
S
O
C
I
A
L
E
C
O
N
O
M
I
C
A
L
C
U
L
T
U
R
A
L
P
S
Y
C
H
O
L
O
G
I
C
A
LF
A
C
T
O
R
S
(
I
n
c
l
u
d
i
n
gpoverty,illiteracy,Ignorance,poor
livingcondtionO
v
er
c
r
o
w
d
ingetc)
social

T
U
B
E
R
C
U
L
O
S
I
SI
SN
O
TM
E
R
E
L
YD
U
ET
O
T
U
B
E
R
C
L
E
B
A
C
I
L
L
I
…
Factorssuchas-
• Poverty,
• O
v
e
r
c
r
o
w
din
ga
n
d
• Malnutrition
Contributetooccurrenceoftuberculosis
social

N
o
w it is recognized that a disease is not only
causedb
yanorganismbutalsopredisposedb
ym
a
n
y
factorscontributingtoitsoccurrence.
Forexample:-“
M
o
d
e
r
nDiseases”ofcivilizationlike–
lungcancer,diabetes,coronaryheartdiseasean
dmental
illnessetchasseveralcontributingfactorsbehindfor
thereoccurrence.
social

I
tisn
o
wk
n
o
w
nthatdiseasessuchasCoronaryheart
diseasea
n
dcancerareduetomultiplefactors.
ForExample-
Excess of fat (saturated) intake, S
m
o
k
i
n
g ,lack of
physical exercise a
nd obesity are involved in the
PathogenesisofCoronaryHeartDisease
M
o
s
tofthesefactorsarelinkedtoLifestyleandh
u
m
a
n
b
e
h
a
v
i
o
r
.
social

Groupor
Popullations
andtheir
C
h
arcteristics
E
n
v
io
rn
m
e
n
t,B
e
h
a
v
io
u
r,
Culture,
PhysiologicalFactors,
EcologicalElements
CausativeFactors
T
I
M
E
social

Thism
o
d
e
lofdiseasecausationwassuggestedb
y
M
a
c
m
a
h
o
nan
dP
u
g
hintheirb
o
o
k
:Epidemiology
:Principlesan
dM
e
t
h
o
d
s
Thism
o
d
e
lis ideallysuitedinthestudyofchronic
disease,w
h
e
r
ethediseaseag
en
tisoftennotk
n
o
w
n,but
istheo
u
t
c
o
m
eofinteractionofmultiplef
a
c
t
o
r
s
…
social
W
E
BOFC
A
U
S
A
T
I
O
N

 T
h
e “
w
e
b
social
of causation” considered a
ll th
e
p
re
d
isp
osin
g facto
rs o
f a
n
y ty
p
e a
n
d th
e
ir
complexinterrelationshipwitheachother
 T
h
efigureillustratesthecomplexitiesofacasualw
e
b
ofmyocardialinfarctionwhichis b
ynom
e
a
n
s
c
o
mp
l
e
t
e
)

social

 T
h
ebasictenetofep
id
emiolo
gyis tostudythe
clustersofcausean
dcombinationsofeffects
an
dh
o
wtheyrelatetoeachothercasualw
e
b
providesam
o
d
e
lwhichs
h
o
w
svarietyof
possibleinterventionsthatcouldbetakento
reducetheoccurrenceofdisease.
 T
h
eMultifactorialtheoryhelpsustounderstand
thevariousassociatedcausativefactors,prioritize
an
dplanmeasurestocontrolthedisease
social
C
O
N
C
L
U
S
I
O
N

EPIDEMIOLOGICAL TRIAD VED (1).pptx

Recommended

Recommended

More Related Content

Similar to EPIDEMIOLOGICAL TRIAD VED (1).pptx

Similar to EPIDEMIOLOGICAL TRIAD VED (1).pptx (20)

Recently uploaded

Recently uploaded (20)

EPIDEMIOLOGICAL TRIAD VED (1).pptx