When selecting mitigation measures for an HIA, high priority should be
given to interventions with a positive impact on the general health status and
less emphasis should be given to disease specific interventions. The investment
in basic health services is likely to have a greater long-term effect than
costly independent disease-specific control interventions. This approach will
improve the cost-benefit ratio of the proposed control measures and improve
on their long-term sustainability (WHO 1993). Interventions with a positive
effect on both the health status and agricultural production, e.g. good water
management and consistent canal maintenance, will likewise improve the
cost-benefit ratio.