In December 2010 Fish Health Inspectors from the Centre for Environment, Fisheries and Aquaculture Science (Cefas) inspected a sample of native European flat oysters (Ostrea edulis) from the River Fal, Cornwall. This followed reports that they were not thriving in the area. The sample was taken from an area already subject to longstanding controls due to the presence of Bonamia ostreae and high levels of this disease were found in the sample. However a related parasite, Bonamia exitiosa has also been confirmed as present in a single animal from this sample.

This is the first record of Bonamia exitiosa in the UK and the disease is currently listed in legislation as exotic to the European Union. B.exitiosa has also been reported in Spain, France and Italy.

Cefas acting on behalf of Defra has issued a confirmed designation and you must apply to the Fish Health Inspectorate for permission if you wish to move any oysters out of or into the area, including movements into purification centres (depuration plants). Additionally:

• You must continue to notify the Fish Health Inspectorate of any increased or unexpected mortality observed in shellfish stocks.
• Confirmed Designation number CD Area 01 issued on 27 March 2009 for the control of Bonamia ostreae in Ostrea edulis (native oysters) remains unaffected by this notice.

Further information about B.exitiosa is available at: www.efishbusiness.co.uk/bonamia-exitiosa/bonamia-exitiosa-q&a.pdf

There are no implications for human health.

Any suspicion of the presence of B.exitiosa should be immediately reported to:

The Fish Health Inspectorate, Centre for Environment, Fisheries and Aquaculture Science (Cefas).
Tel: 01305 206700
E-mail: fhi@cefas.co.uk

Notes to editors:

• CD01/2011, issued under the Aquatic Animal Health (England and Wales) Regulations 2009 restricts the movement of any oysters from within the designated area without the prior written consent of the Fish Health Inspectorate at Cefas.
• Clinical signs of the disease may include poor condition, poor growth rates, gaping, loss of liquor and watery flesh. These signs usually appear when water temperatures exceed 160C.
• Further information is available at www.efishbusiness.co.uk, or from Cefas, Fish Health Inspectorate, The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB. Tel: 01305 206700 or e-mail: fhi@cefas.co.uk

Press contact: Anne McClarnon: 01502 524370 / anne.mcclarnon@cefas.co.uk