1 over the
ransCube
ld Health
] includes
the left).
iges from
iches and
ng optical
1 politics,
yuidelines
variability
ive early
quires the
azards +
include
tical and
hematical
uiring all
p being a
ology has
nitor and
s diseases
'onmental
satellite-
T-image),
nography
1ydrology
data from
predictive
CASE
ach have
he Ferlo
lead the
id extend
cattle are
VF in the
infected
nd Culex
re et al,
breaks in
perinatal
oms may
norrhagic
graphical
007) and
letect the
areas at
risks: the so-called Zone Potentially Occupied by
Mosquitoes (ZPOM).
The integrated approach to determine the environmental
risk levels of RVF (CNES, 2008) bridges the physical
and biological mechanisms, linking environmental
conditions to the production of RVF vectors and the
accompanying potential risks.
Possible hazards in the vicinity of fenced-in hosts are
displayed in the second Figure, where the mapped ZPOM
is displayed. In the Figure the Zone Potentially Occupied
by Mosquitoes, or ZPOMs with ranked hazards from
yellow (low hazards) to red (high hazards). ZPOM in the
Barkedji area (large black area) is obtained from the
ponds distribution after a single rainfall event (top left).
Localization of the Barkedji village and ruminants'
fenced-in areas (vulnerability, from QuickBird) in black
for the same area (top right). Potential risks ie., —
hazards + vulnerability are shown by super-imposing the
two pictures (bottom of Figure).
Parks
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
Vulnerability
V
| Risks
IV. CONCLUSIONS
Climate variability and change and environmental risks
comprise mechanisms linking rainfall variability and
trends, density of vectors/mosquitoes and their
aggressiveness, and hosts vulnerability. The dynamical
evolution of ZPOMs, from ponds clustering, has
identified risks as a function of discrete and productive
rainfall events. The socio-economic risks can thus be
anticipated based on statistical evaluation of the seasonal
rainfalls which can be done a few months prior to the
rainy season (based upon seasonal forecasts).
Impacts mitigation can be accomplished though strategic
displacement of the fenced-in animals during the course
of the rainy season, vaccination, destruction of vectors.
The Transcube Model and the conceptual approach
presented here are to be linked with biological modelling
of virus transmission and circulation, as well as with
classical epidemiological models. Ultimately, the fully
integrated approach should help understanding the
mechanisms leading to potential RVF epidemics and
improve related EWS or “RVFews”.
The physical and biological mechanisms from other
infectious diseases are to be developed by applying a
similar methodology elsewhere (including higher-latitude
regions) where climate and environment are also varying
and changing rapidly. This is in the process of being
implemented for Malaria epidemics over Burkina Faso
(PaluClim project).
V. REFERENCES
CNES, 2008 : Method for tele-epidemiology (Méthode
pour la télé-épidémiologie). Patent pending f
PCT/FR2009/050735.
Lacaux J-P., Tourre Y. M., Vignolles C., Ndione J-A.,
Lafaye M., 2007 : Classification of ponds from high
spatial resolution remote sensing: application to rift
valley fever epidemics in Senegal. J. Remote Sensing
Env., 106, 66-74.
Lafaye M., 2006 : Nouvelles applications spatiales pour
la santé: la télé-épidémiologie pour le suivi des fiévres
aviaires. CNES Magazine, February, 30-31.
Martens, P. 2001: Climate Change: Vulnerability and
Sustainability. IPCC TAR report.
www.erida.no/climate/ipec. tav/we2/539.htm
Plan Bleu, 2008 : Mediterranean Basin: Climate Change
and Impacts during the 21st century. Report 2008, Le
Plan Bleu, Sophia Antipolis, 15 Rue Beethoven, 06560,
pp 67.
Takken, W., 2006 : Environmental Change and Malaria
Risk: Global and Local Implications. Springer Edit.
pp150. ISBN-13: 978-1402039270.
Tourre Y. M., White W. B., 2006 : Global climate signals
and equatorial SST variability in the Indian, Pacific and
Atlantic oceans during the 20th century. Geophys. Res.
Lett., 33, L06716, doi: 10.1029/2005GL025176.
Tourre Y. M., Fontannaz D., Vignolles C., Ndione J-A.,
Lacaux J-P., Lafaye M., 2007 : GIS and high-resolution
remote sensing improve early warning planning for
mosquito-borne epidemics. Healthy GIS, GIS for Health
and Human Services, ESRI, 1-4.
Tourre Y.M., Lacaux J-P., Vignolles C., Ndione J-A.,
Lafaye M., 2008 : Mapping of zones potentially occupied
by Aedes vexans and Culex poicilipes mosquitoes, the
main vectors of Rift Valley Fever in Senegal. Geospatial
Health 3 (1), 69-79.
Vignolles C., Lacaux J-P., Tourre Y. M., Bigeard G.,
Ndione J-A., Lafaye M., 2009 : Rift Valley fever in a
zone potentially occupied by Aedes vexans in Senegal:
dynamics and risk mapping. Geospatial Health 3 (2),
211-220.
