Abstract
As the size and intensity of aquaculture enterprises increase in this millennium, so will the scale for potential loss from disease. Economies dependent on them for export earnings will be vulnerable to disastrous epizootics that must be avoided by implementation of appropriate safeguards. These should be based on a scientific determination of disease transfer risks and be designed to have minimum impact on international trade. The risk assessment process outlined by the WTO SPS agreement exemplifies this approach. We will illustrate the issues on preventing the spread of fish and shellfish diseases based on our experience with two shrimp viruses (IHHNV and WSSV). The greatest risk for disease spread lies with careless movement of living animals for aquaculture. Other risks will also be reviewed. Ultimately, intensive aquaculture will move towards closed recycle systems based on domesticated and genetically improved stocks. The impetus for this will come mostly as a result of pressure from national trade requirements concerning human and veterinary health risks, and from consumer groups concerned about the environment and animal welfare.
