DNA vaccination in aquaculture — Expert judgments of impacts on environment and fish health

In this expert elicitation twelve Norwegian scientists were interviewed about environmental and health consequences of DNA vaccination in aquaculture. The intention was to elicit scientists’ judgments of potential sources of uncertainty associated with the use of DNA vaccines. Emphasis was put on three incidents: i) immune response following the DNA vaccination, ii) tissue distribution and expression of the injected plasmid DNA (pDNA) and iii) environmental release of DNA vaccines. We present what the experts identified as potential consequences of introducing DNA vaccines to aquaculture. Our findings support the need for more research on the stability of the pDNA, unintended immunological impacts and integration of the pDNA in the genome of the recipient organism. The study suggests that expert elicitation can improve communication of scientific uncertainty and thereby advance the scientific discussion. We argue that our findings support the importance of including several experts in the process of risk assessment and decision support, as different scientists express diverging opinions of the consequences involved.