Environmental safety assessment of vaccines derived from biotechnology.

Products derived from biotechnology are generally safer than previous products obtained by conventional, more empirical methods. Given the great variety of biotechnology-derived products and use situations, risk assessment procedures must be based on a case-by-case analysis. It is therefore difficult to propose a generic, well-defined risk assessment procedure. In the case of vectored vaccines, two main risks must clearly be assessed: the possible risk of tissue or species tropism modification, with special regard to non-target species, the risk of recombination with wild counterparts of the vector. This paper begins with a classification and description of the main biotechnology-derived products to be used in veterinary medicine, including deoxyribonucleic acid (DNA) vaccines, and then attempts to define general rules for the risk assessment of each category of products.