Training of Trainers - Library - Network of Aquaculture Centres in ...

pathogen transfer is generally considered greater for movement of live aquatic animals than for movement of deadproduct. Irrespective of disease risks involved, aquaculture and global trade will continue to intensify and expand.The WTO-SPS Agreement sets out the basic rules for food safety and animal and plant health standards. Thebasic aim of the SPS Agreement is to maintain the sovereign right of any government to provide the level of healthprotection it deems appropriate, but to ensure that these sovereign rights are not misused for protectionistpurposes and do not result in barriers to international trade.Aquatic Animal HealthInfectious diseases are still considered as one of the serious challenges to sustainable aquaculture in many partsof the world, including Asia. In Asia, diseases of aquatic animals and bio-security measures for managing risks ofaquatic animal disease outbreaks have received less attention than livestock diseases. This is despite the fact thatAsia is a major exporter of aquatic animal products annually worth several million US$. Aquaculture (e.g. shrimp,scampi, carp and catfish) already makes a significant contribution to rural development, poverty reduction, foodsecurity, economic development and trade throughout Asia, and can make further substantial contributions.The epidemic spread and devastating impacts of aquatic animal diseases such as epizootic ulcerative syndrome(EUS) in freshwater fish; viral nervous necrosis (VNN) in marine fish; white spot syndrome virus (WSSV) inpenaeid shrimps; white tail disease (WTD) in Macrobrachium rosenbergii and the emerging Taura syndrome virus(TSV) and Infectious myonecrosis virus (IMNV) in Penaeus vannamei; in Asia have clearly demonstrated thevulnerability of aquaculture systems to infectious disease emergencies. More recently, the widespread massmortalities of koi and common carp in Indonesia and Japan due to infection with koi herpes virus (KHV) have reemphasizedthe impact that emerging diseases can have on local economies and sustainability of the aquaculturesector. The increasing globalization and trade volume of the aquaculture sector has created new mechanisms bywhich pathogens and diseases may be introduced or spread to new areas. Known and unknown diseaseproblems may arise quickly in any country’s aquaculture sector, often with serious economic, social and ecologicalconsequences, but may be difficult or impossible to eliminate once established.Some of the key disease control strategies applied globally include;• Preventive and prophylactic strategies (e.g. vaccination)• Specific pathogen free (SPF) and specific pathogen resistant (SPR) based aquaculture systems• Implementation of national aquatic animal health strategies• Biosecurity programs• Epidemiological approaches• Risk analysis and management• Rapid diagnostics• Early warning surveillance• Co-operative industry-wide effortsBio-securityBiosecurity is a new term for an old concept. There is no single definition for biosecurity. However, biosecurity canbe defined as a set of standard scientific measures, adopted to exclude pathogens from culture environment andhost and, more broadly, to limit pathogen establishment and spread. Some concepts vital for biosecurity areidentification of pathogen entry routes, quarantine and screening of hosts introduced in the system, disinfection atdefined critical control point, restricted access and identification of risk factors which favour pathogenestablishment and spread. A biosecure system could therefore be based on specific pathogen-free stocks,including enclosed, reduced water-exchange/increased water-reuse culture systems, biosecure managementpractices, and co-operative industry-wide disease control strategies.16