Pre-emptive and non-invasive pathogen diagnostics to prevent the spread of shellfish disease (FS042)

Project Outcome:

Disease is the single biggest issue facing oyster aquaculture and restoration. Measures to stop the spread of oyster diseases in the UK rely entirely on the prevention of animal movement from disease positive to disease free sites. However, these measures are not entirely successful and have seen recurrent failures in recent years, resulting in gradual spread of pathogens across the UK.

This project demonstrated the ability of a new non-invasive diagnostic process, which can be used prior to moving shellfish between sites. In brief, following a short incubation of oysters in a quarantine tank we have shown that it is possible to detect Bonamia ostreae and OsHV-1 DNA directly from environmental substrates in the tank using highly portable battery powered equipment. For Bonamia in particular, this process appears to be very sensitive; our initial work has demonstrated accurate detection of a 4% infection rate in the population, and we predict from this data that the actual limits of detection are considerably more sensitive.

This process now requires refinement and further validation, after which it will be tested in field scenarios by aquaculture practitioners. This will enable positive action beyond legislative requirements, to keep oyster farms and restoration sites disease-free and prevent further disease spread. This methodology delivers a scale of effective and timely testing and disease control otherwise unachievable.