-B8, 2012
mate Data like
emperature,
lumidity etc.
CARTOSAT -1
en rectified using
tracted. Different
r enhancement,
| on the satellite
ve been merged
ility. Land use /
ing supervised
ellite data. False
rous wetlands in
Vegetation index
igour of the area
he vicinity
SS IV covering
ax & Min) and
cropping pattern,
density of vector
listrict have been
HD and disease
and inter-annual
as been a steady
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B8, 2012
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia
increase in the annual number of disease cases. The Annual
vector density of P.argentipes is reflected in the form of two
peaks. Disease epidemic starts at summer and peaks in the
March - April and major peak is seen in August-September
[1,3]. Dry and humid with higher temperature is favourable
climatic condition to the vector in the endemic area. Table - 1
shows population affected and death occurred in twelve blocks
of Vaishali district which is reported in Public Health Centres
during the years 2008-2010[9]. The population at risk in Mahua
block indicates the maximum of 419, 198 and 191 respectively
during the years 2008-2010. It is also observed that a large
number of disease incidence is not reported in the PHCs
regarding disease incidence of the study area.
Name of the 2008 2009 2010
Block Affected Death Affected Death Affected Death
Hajipur 206 0 129 0 133 0
Bidupur 126 0 85 1 82 0
Vaishali 275 0 195 1 185 1
Goraul 166 1 80 0 95 1
Mahannar 120 0 98 0 91 1
Mahua 419 0 198 0 191 1
Lalganj 241 0 150 0 106 0
Sadai Buzurg 99 0 75 0 95 0
Jandaha 204 0 99 0 105 0
Patepur 198 0 151 0 97 0
Raghopur 385 1 302 0 368 0
Sadar Hospital 348 1 321 2 441 3
Total 2787 3 1883 4 1989 7
Table 1- Disease incidence in various Blocks / PHC of
Vaishali District
Multivariate Analysis: A Systematic study of geo-
environmental parameters derived from satellite data in
conjunction with ground intelligence enabled modelling of
infectious disease and risk villages. High resolution Indian
satellites data of IRS LISS IV (multi-spectral) and Cartosat-1
(Pan) have been used for studying environmentally risk
parameters viz. peri-domestic vegetation, dwelling condition,
wetland ecosystem, cropping pattern, Normalised Difference
Vegetation Index (NDVI), detailed land use etc towards risk
assessment. Univariate analysis of the relationship between
vector density and various land cover categories and climatic
variables suggested that all the variables are significantly
correlated. Using the significantly correlated variables with
vector density, a seasonal multivariate regression model has
been carried out incorporating geo-environmental parameters,
climate variables and seasonal time series disease parameters.
Linear and non-linear models have been applied for periodicity
coeff p-value
correlation
108(0.063)
Table 2: Statistical analysis of endemic and non-endemic
area
and inter-annual temporal scale to predict Man-hour-density
(MHD). Out-of-fit data have been used for validating the model.
Multivariate regression analysis has been carried out using geo-
environmental parameters and climatic variables and derived
coefficients are shown in equation below.
Multivariate Regression Equation for Vector MHD
Z = - 42.23 + (Temp. x 0.597) + (Humd. x 0.684) —
(Dry fallow x 0.170) + (Min. NDVI x 11.44)
Where, Z is the estimated man-hour-density.
The statistical analysis of the parameters indicate that average
maximum temperature, humidity, settlement with vegetation,
dry fallow, moist fallow, minimum NDVI are significantly
correlated with MHD (Table-2).
GIS Model: The patterns in the dynamics of the vector diseases
are their periodicity and seasonal and inter-annual temporal
scale forms the basis for the development of Early warning
system [7]. Satellite data forms the primary input for generation
of geo-environmental parameters. The following data sets have
been generated using satellite data processing /digitisation and
organised in the GIS environment( Table 3).
1| Base layers consisting of road, rails, village
locations and administrative boundaries like village
boundary, block / taluk boundary, district boundary
etc
Land use / land cover map
Normalised Difference Vegetation Index
Soils (type, ph etc)
Peri-domestic vegetation
Cropping pattern (crop calendar, crops etc)
Hydro-meteorological data (rain fall, humidity,
temperature etc)
Disease Vector (MHD, incidence etc)
9| House survey (Nature of the house, domestic
animals, roofs, type of walls etc.)
Aal SION
oo
Table 3 — List of variables used for the analysis
To improve the MHD predictive approach, fuzzy model has
been developed and incorporated in GIS environment
combining spatial geo-environmental and climatic variables by
applying a Boolean logic for the members of the membership
function and the equation is given below.
The combined Fuzzy membership function is defined as
u = (Fuzzy algebraic Sum) Y * ( Fuzzy algebraic Product ) FM
n
Fuzzy algebraic sum z 1- II. (1- pi)
i=1
n
Fuzzy algebraic product = IT (Hi)
i=
where p ; is the fuzzy membership for ji” map and i=
1,2,3,......n maps are to be combined and where yi combined
fuzzy membership of Y operation, Y is the parameter chosen in
the range of (0,1) such that when Y is 1, the output of combined
fuzzy membership value equals to same as fuzzy algebraic sum
and when Y is 0, the combination equals to the fuzzy algebraic
product. Therefore, a judicial choice of Y factor produces
output values that ensure the compromise between increasive
tendencies of the fuzzy algebraic sum and the decreasive effect
of the fuzzy algebraic product. Jeyaram, (2008) has used the
above techniques successfully in prioritising water conservation