English Abstract One of the potential health consequences of global
warming is a (re-)introduction of vector-borne diseases into certain regions
which may, or may not have been, previously endemic. In most tropical
countries, such diseases are a major cause of illness and death. One of the
most important among them is schistosomiasis, which is associated with one
of three species of parasite each of which are transmitted by a specific
snail (intermediate host). Temperature and precipitation changes would
directly affect the behaviour and geographical distribution of the vectors
and the development of the parasites. Climate change could also have an
indirect effect by influencing environmental factors such as vegetation and
the availability of breeding sites. The direct effects of a change in
temperature and precipitation on the transmission potential of the snail
population and the consequent effects on human health is evaluated by
assessing the change in potential schistosomiasis risk areas and the change
in world schistosomiasis prevalence. General Circulation Model based
scenarios of anthropogenic global climate change are deployed in the
assessment of potential changes in areas vulnerable to the transmission of
schistosomiasis. The study shows that the transmission potential of this
vector-borne disease is, although to a lesser extent than malaria, very
sensitive to climate changes on the periphery of the present endemic areas
and at higher altitudes within these areas. The health impact will be most
pronounced among populations living in the economically less developed
temperate regions in which endemicity has previously been low or absent. In
more developed areas it is expected that no major problems will occur since
effective control measures are economically feasible as transmission
potential would increase.
