The Asia Regional Advisory Group on Aquatic Animal Health meets annually to discuss regional disease issues including emerging disease threats. This is the report of the fourth meeting, held 22-24 October 2005 in Colombo, Sri Lanka. The report discusses emerging disease problems and regional response to:

• Finfish diseases: The spread of koi herpes virus, emerging diseases such as red spot disease in grass carp, streptococcosis caused by Streptococcus iniae and S. agalactiae, nocardiosis caused by Nocardia seriolae, Vibrio spp., Tenacibaculum maritimum infection in marine fish.
• Crustacean diseases: Taura syndrome virus, white body disease, slow growth syndrome and Mourilyan virus in penaid shrimp; white tail disease in Macrobrachium rosenbergii. 
• Mollusc diseases: Abalone viral mortality, Marteilioides chungmuensis, Marteilia sydneyi, viral gametocytic hypertrophy, herpes virus of oysters, Bonamia exitiosa.

Other issues discussed include:

• Outcomes of the OIE General Session and Aquatic Animal Health Standards Commission meetings in 2005, including adjustments to the list of notifiable diseases.
• A review of the regional aquatic animal health reporting system, including the list of reportable diseases.
• Progress in implementation of the the Regional Technical Guidelines on Health management for the Responsible Movement of Live Aquatic Animals.
• Identification and designation of regional aquatic animal health resources, including experts, centres and reference laboratories.
• Regional and international cooperation.