All you ever wanted to know about shellfish diseases and didn’t dare to ask

1. All you ever wanted to know about shellfish diseases and didn’t dare to ask - it's not as complicated as you might think Ian Laing

2. Some oyster diseases Dutch shell disease Oyster Velar virus disease Haemocytic Infection Virus Disease MSX Denman Island Disease Haemocytic Neoplasia "Dermo" Disease Marteilioides chungmuensis Marteiliosis (Aber Disease) Bonamiasis Gill disease Microsporidiosis SSO Viral Gametocytic Hypertrophy Juvenile oyster disease Herpes-Type Virus Disease Oyster Egg Disease Red Worm Disease Perkinsus Nocardiosis Oyster Trematode Diseases

3. List of Diseases 57 oyster diseases 34 clam and cockle diseases 25 mussel diseases 16 abalone diseases 24 scallop diseases 85 crustacean diseases Bower, S.M. and McGladdery, S.E. (2003): Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish URL: http://www-sci.pac.dfo-mpo.gc.ca/shelldis/title_e.htm

4. The Single European Union Market • Animal health conditions for placing aquaculture animals on the market ~ EC Directive 91/67, as amended.

5. Europa Animal Health and Welfare Web site

6. Listed diseases - THEN

7. OIE - International Organisation for Animal Health Aquatic Animal Code and Manual

8. Listed diseases - NOW

9. Aimsof the legislation • Prevent the spread of serious disease • Allow trade • This means • Controlling the movement of shellfish • Import and export checks

10. Bonamiasis • Introduced into Europe in 1979 - Brittany Bonamia ostreae is an intracellular plasmodial protozoan parasite (2-5m) that belongs to the Haplosporidium group. It affects the granular blood cells (haemocytes) of flat oysters.

11. Bonamia ostreae Web site – www.bonamia.com Google – 14,000 results ASFA – 168 papers Project BOLCI Shellfish News

12. Zones in Great Britain • EU Health Rules (91/67/EEC) • UK programmes approved (92/528/EEC) • Approved Zones (2002/300/EC) 1993 – 2005 3 infected areas 2006 - Loch Sunart (E) and Milford Haven (F) 2007 – West Loch Tarbert (G) 2008 – North Kent

13. Meanwhile, in Ireland 1993 - 2002 2003 – Achill Sound and Blacksod Bay 2005 – Lough Foyle 2006 – Lough Swilly 2008 - Strangford Lough

14. “Placing on the market” (2006/88 continued) • Authorisation of Aquaculture Production Businesses • includes dispatch and purification centres • Susceptible and vector species • Risk-based surveillance • for increased mortality

15. Surveillance for mortality

16. Marteilia refringens One species? Two types? Marteilia (type M) in mussels in Southampton Water (and elsewhere)

17. Pacific oysters • Oyster Herpes Virus • Vibrio splendidus • Environmental factors “Summer mortality” 500 μm

18. 85 crustacean diseases Listed diseases - NEW

19. White spot disease (WSD) • Global spread via live and frozen animal movements – 100% mortality in days – no effective treatment • Can be transmitted to European decapods (crayfish, crabs, lobsters) • Experimental infection of European lobster via feeding of WSD-infected prawns • Causes disease within the European water temperature range • Little research into vectors/carrier hosts

20. White spot disease (WSD) • IS THERE A THREAT IN EUROPE? • Small crustacean aquaculture industry • Large and very valuable marine fishery for prawns, lobsters and crabs • Potential routes of entry of WSD to Europe – larvae or broodstock for aquaculture, imported fresh and frozen prawns or live potentially carrier species for consumption • Significant movement of fresh, frozen and live European crustaceans within the EU

21. I hope that was not too complicated Note: None of these diseases affect humans