Chief Veterinary Officer, Patrick J. Rogan has informed the World Organisation for Animal Health that 14 bays have been hit.
All cases have been found in farmed open, coastal water.
Mortalities have been considerable, particularly in seed. Half grown and adult oysters have also suffered mortalities in some areas though at lower levels.
Transmission from site to site as well as through the water is believed to be occurring but the presence of the virus in all of these areas last year and the possibility of latency makes it impossible to be sure whether the source is introduction of stock from an infected area or as a result of latent infections in existing populations.
Although mortalities now appear to be at an end, reinfection of stocks which will be introduced between now and next summer is anticipated once the temperatures begin to climb again in June.
The virus was detected between 3 June 2010 and 5 August 2010 in all 14 bays using polymerase chain reaction and histopathology examination.
Suspected Ostreid Herpes Virus
IRELAND - It is suspected that ostreid herpes virus is the cause of death of pacific oysters in Ireland.
