9.11.2. Malaria Epidemics
Malaria prevention illustrates approaches to adaptation that also apply to
other vector-borne disease threats. To reduce the increased risks of malaria,
human populations must take adaptive measures to diminish the impacts. Although
malaria epidemics can be triggered by changes in meteorological or socioeconomic
conditions, many health services fail to monitor these variables because indicators
of risk for epidemic-prone areas have not been determined (Najera et al., 1998).
Malaria surveillance and epidemic preparedness may benefit from recently developed
tools that predict the seasonality and risks of epidemics by using satellite
or ground-based meteorological data (e.g., Hay et al., 1998; Patz et al., 1998b).
New approaches to mapping the distribution of malaria vectors over large areas
may facilitate species-specific vector control activities. It has been shown
in western Kenya that the risk of malaria transmission in the highlands can
be predicted with a simple rainfall- and temperature-dependent predictive model
(Githeko et al., 2000).
Epidemics are focal in nature and often may be controlled by limited application
of safe and effective residual insecticides. Parasite resistance to antimalarials
is a threat to malaria control programs; therefore, it is essential that drug
sensitivity is reviewed regularly. At the personal level, insecticide-protected
fabrics (e.g., bednets) have been shown to be effective against infective mosquito
bites (Legeler, 1998).