Report of the technical hearing meeting on Epizootic Ulcerative Syndrome (EUS) 1

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1 EFSA Journal 2011;9(10):195 TECHNICAL REPORT OF EFSA Report of the technical hearing meeting on Epizootic Ulcerative Syndrome (EUS) 1 European Food Safety Authority 2, 3 European Food Safety Authority (EFSA), Parma, Italy SUMMARY On 01 December 2010, EFSA received a request from the European Commission (EC) for a Scientific Opinion on Epizootic Ulcerative Syndrome (EUS). The EC mandate specifically requested to assess: 1) the risk of introduction of EUS in the European Union (EU) by means of import from third countries, 2) the risk of EUS to spread and persist within the EU and 3) the possible significance and impact in the European Aquaculture taking account of the epidemiology, the available diagnostic methods, the susceptible species range, and the relevant environmental conditions. A technical hearing with relevant stakeholders and experts was held at EFSA s premises in Parma on 14 June Participants were invited to present and submit any scientific information and documentation, considered to be relevant for the Scientific Opinion. Participants were also involved in a review of the approach taken by the adhoc Working Group for the Import Risk Assessment (IRA). The meeting had the following terms of reference: i) Review proposed introduction pathways ii) Review the available data regarding epidemiology and current global distribution of EUS and trade-related data and assess its suitability for the proposed assessment iii) Collect information/expert opinion suitable for the development of the consequence assessment requested to EFSA iv) Assess current practices for surveillance, prevention and control of the infection/syndrome in particular concerning ornamental fish. This report is a summary of the issues discussed during the meeting. During the meeting the participants agreed with the general assumptions of the Working Group, with regards to the proposed introduction pathways. Information on the level and type of surveillance in various countries is usually absent. The capacity for diagnosing EUS varies considerably in infected countries. The participants were not aware of any monitoring program for EUS in the EU focusing on ornamental fish and the intra-community trade of ornamental fish is not documented. Awareness of the disease by aquaculture producers is considered low. The risk of spread into aquaculture facilities is considered to be higher through contaminated water, than live fish movements into farms. European Food Safety Authority, On request from EFSA, Question No EFSA-Q , issued on 6 October Correspondence: ahaw@efsa.europa.eu 3 Acknowledgement: EFSA wishes to thank the members of the Working Group on Epizootic Ulcerative Syndrome: Hans- H. Thulke and Birgit Oidtmann for the preparatory work on this scientific output and, the hearing experts: Niels Jorgen Olesen, Guenther Kotterba, Melba Reantaso and the observers: Alex Ploeg and Andrea Fabris and EFSA staff: Ana Afonso for the support provided to this scientific output. Suggested citation: European Food Safety Authority; Report of the Technical Hearing Meeting on Epizootic Ulcerative Syndrome (EUS). EFSA Journal 2011;9(10):195. [16 pp.] doi: /j.efsa Available online: European Food Safety Authority, 2011

2 KEY WORDS Epizootic Ulcerative Syndrome, Technical hearing meeting, Import risk assessment. EFSA Journal 2011;9(10):195 2

3 TABLE OF CONTENTS Summary... 1 Table of contents... 3 Background... 4 Terms of reference... 4 Consultation Consultation with Animal Health and Welfare Network Technical hearing meeting Objectives Participants Main issues discussed Distribution of EUS world wide What is confirmed /non confirmed? Current situation in Australia, South East Asia and other parts of the world Significance of the recent Canada outbreak Introduction pathway investigations in historic outbreaks? Other information sources about EUS infected areas? Actions taken in infected countries? Have trade/movement restrictions being taken? Current trade practices and trade volumes of Ornamental fish How are suppliers of ornamental fish evaluated? Are there significant differences between how trade (import and internal distribution) is done in different countries? Trade volumes Quarantine, is it happening, for how long, which species and how? Are there any open ornamental facilities registered in the EU? Are we aware of a EU registry of closed ornamental facilities? Pathways for introduction Sensitivity of overall surveillance system in infected countries Detection of EUS at the Border Inspection Point Controls at wholesaler facilities Release assessment Spread and persistence What is the potential that EUS could be unrecognised? What are the chances to detect EUS clinically? Is the aquaculture industry taking measures to protect farms against EUS introduction? Impact What preparation was undertaken by the ornamental fish industry for the implementation of the Directive concerning EUS? Are there any studies on the possible impact of EUS to EU aquaculture? What would it mean for EU aquaculture if the EU or one of its member states was no longer EUS free? Trends in aquaculture cultured species? References Abbreviations EFSA Journal 2011;9(10):195 3

4 BACKGROUND On 01 December 2010, EFSA received a request from the European Commission (EC) for a scientific opinion on Epizootic Ulcerative Syndrome (EUS). EFSA accepted the Mandate and its Terms of Reference on 15 December 2010 (M ). The background and terms of reference of the mandate received from the European Commission is available on the EFSA register of questions 4. The EC mandate specifically requested to assess: 1) the risk of introduction of EUS in the European Union (EU) by means of import from third countries, 2) the risk of EUS to spread and persist within the EU and 3) the possible significance and impact in the European Aquaculture taking account of the epidemiology, the available diagnostic methods, the susceptible species range, and the relevant environmental conditions. A scientific ad hoc Working Group (WG) was established to develop the requested risk assessment taking in consideration all available scientific data on the issue. Large data gaps, in particular concerning trade and animal health monitoring of ornamental fish imports into the community, were previously identified (2010, Dataquest 5 ). Furthermore, it was recognised that expert opinion would be advantageous in order to conduct the consequence assessment requested. Contact was established with all Member States through the Animal Health and Welfare Network on 14 January 2011 by . The AHAW network representatives were asked to present and submit any scientific information and documentation, considered to be relevant for the Scientific Opinion, but also to express their interest in a future participation on the development of the assessment. A technical hearing meeting with relevant stakeholders and experts was also held at EFSA s premises in Parma on 14 June The meeting was organised by AHAW in the context of the ad hoc WG. Participants were invited to present and submit any scientific information and documentation considered to be relevant for the Scientific Opinion. Participants were also involved in a review of the approach taken by the ad hoc WG for the Import Risk Assessment (IRA) and to express their expert opinion. EFSA invited the AHAW Unit to prepare a meeting report containing all matters discussed (M ). The publication of this technical report is synchronous with the publication of the Scientific Opinion. TERMS OF REFERENCE A technical hearing meeting was organised with the following terms of reference: Review proposed introduction pathways. Review the available data regarding epidemiology and current global distribution of EUS and trade-related data and assess its suitability for the proposed assessment. Collect information/expert opinion suitable for the development of the consequence assessment requested to EFSA. Assess current practices for surveillance, prevention and control of the infection/syndrome in particular concerning ornamental fish EFSA Journal 2011;9(10):195 4

5 CONSULTATION 1. Consultation with Animal Health and Welfare Network The AHAW Network is based on the Decision concerning the establishment and operation of European Networks of scientific organisations operating in the fields within the Authority s mission 7. In accordance with Article 22 (7) and 23 of the Regulation, the Authority shall promote the networking of scientific organisations of EU Member States (MS) operating in the fields within the Authority's mission. These include inter alia; facilitating the development of a scientific cooperation framework by the coordination of activities, the exchange of information, the development and implementation of joint projects and the exchange of expertise and best practices in the fields within the Authority's mission. The AHAW Network was contacted on 14 January 2011 by . The EC mandate requesting a scientific opinion on EUS was communicated and the focal points were asked to present and submit any scientific information and documentation considered to be relevant for the Scientific Opinion. Replies were received from Denmark and Germany. The two replies concerned the existence of ongoing research projects on EUS. 2. Technical hearing meeting 2.1. Objectives The overall objective of the Meeting was to exchange views in relation to the risk assessment developed by the ad hoc WG and to request additional data and expert opinion on the issue Participants The AHAW panel ad hoc WG, identified stakeholders with interest on the risk of introduction, spread and establishment of the disease and able to provide additional relevant information for the assessment. The WG elaborated a meeting agenda with a list of points to be discussed. The agenda was relevant for technical and scientific representatives of the ornamental fish industry, European Aquaculture producers, research groups and institutions. EU Member States and European Commission representatives were also invited. A total of 7 people representing 7 different organisations attended the meeting. Also, one expert of the Working Group and the Chair of the EFSA Working Group on EUS participated in the Meeting. The list of meeting participants is presented in Table 1. Table 1: List of participants Hans- Herman Thulke Birgit Oidtmann Niels Jorgen Olesen Guenther Kotterba Melba Reantaso Alex Ploeg Andrea Fabris Sigrid Cabot AHAW Panel member, EUS WG Chairman EUS WG member Fish Diseases Community Reference Laboratory (CRL) Aarhus, Denmark Federal Institute of Animal Health (FLI), Germany. Food and Agriculture Organization (FAO) Ornamental Fish International (OFI) Federation of European Aquaculture Producers (FEAP) EC Unit G2 Animal Health 7 EFSA Journal 2011;9(10):195 5

6 Stefano Sotgia Ana Afonso Karen Mackay EC Food and Veterinary Office (FVO) EFSA AHAW Unit EFSA AHAW Unit 3. Main issues discussed The EUS WG chairman presented the EFSA mandate and the WG approach. The disease EUS is caused by the oomycete Aphanomyces invadans, the pathogen is the identified hazard. The TOR were translated by the WG following discussions with the requestor into 4 different risk questions: 1. Introduction of the hazard A. invadans with live fish imports into EU aquatic facilities (farms, open ornamental facilities and closed ornamental facilities). 2. Release of A. invadans from the aquatic facility once introduced. 3. Spread and establishment of A. invadans in natural water bodies and aquaculture in European Member States once it was released. 4. The possible significance and impact in the European Aquaculture once spread occurs. Considering the above risk questions, a list of data requirements was elaborated by the WG. The data requirements are summarised in Table 2 for the entry assessment, in Table 3 for the release assessment and in Table 4 for the assessment of spread and persistence. Table 2: Risk of Entry: Steps in entry pathway and data requirements Step in Pathway Information request 1 Country of origin not EUS free % countries exporting ornamental fish to EU that are not EUS free 2 Origin of fish not traceable % fish with given origin vs. fish collected from several wild catchments / unknown rearing farms 3 EUS susceptible species imported % imported fish that are of susceptible species 4 Limited effectiveness of EUS detection at BIP 5 BIP misses the infected consignment 6 Not detected after release from BIP Detection of EUS clinical diagnosis common practice Table 3: Risk of release : Steps in release pathway and data requirements Step in Pathway Information request 1 Release from closed ornamental facilities Registry of closed ornamental facilities 2 Detection of EUS at ornamental fish wholesaler and retailer facilities 3 Control measures at wholesaler and retailer facilities Disease awareness Treatments performed Table 4: Risk of Spread and Persistence: data requirements EFSA Journal 2011;9(10):195 6

7 Step in Pathway Information request 1 Detection of EUS in aquaculture and natural Disease awareness waters 2 Potential that EUS could be unrecognised Diagnostic capacity 3 Control measures on aquaculture facilities Potential spread pathways Several data gaps, as well as uncertainties on the available data, were identified, which allowed for the development of a list of discussion points. The points of discussion were sent to the participants prior to the meeting. Additional questions were formulated to address the issue of significance and impact Distribution of EUS world wide What is confirmed /non confirmed? The EFSA ad hoc WG has reviewed published literature, including the OIE WAHID database, in order to gather information concerning geographical distribution of EUS. The status of disease confirmation or suspicion, according to the definitions of confirmed and suspected cases (OIE, 2011), are not always reported, creating considerable uncertainty. The FAO representative explained that confirmed cases, as presented in previous FAO publications, e.g. the report on the outbreak of EUS in Africa (FAO, 2009) are based on histology evaluation. A member of the working group referred to an EFSA report on susceptible species range for EUS (EFSA, 2008) and explained that criteria developed for assessing the susceptible species range for EUS would require additional information. Confirmation of the identity of the pathogen by molecular methods was necessary to assign a species into Group I (fish species for which scientific evidence supports susceptibility). Where there was partial evidence for susceptibility, but confirmation on the identity of the pathogen was missing, fish species were allocated in Group II. The problem of the lack of information regarding the level of surveillance (and therefore evidence for absence if EUS was not reported) in various countries was discussed. The FAO representative gave a brief overview of the surveillance programmes in South East Asia. In South East Asia where the disease is considered endemic in many countries, a surveillance system (passive surveillance) has been in place since Diagnostic capacity varies considerably between different countries in the region and for that reason the Food and Agriculture Organization of the United Nations (FAO) and the Network of Aquaculture Centres in Asia-Pacific (NACA) (Bondad- Reantaso et.al, 2001) created guidelines for diagnosis but also developed a system where diagnosis confidence can be defined at 3 levels: Level I Diagnosis by clinical observation Level II Diagnosis by histopathology, parasitology, bacteriology and mycology Level III Diagnosis using advanced diagnostic specialisation (immunology and molecular techniques NACA and FAO produces EUS reports as part of the Quarterly Aquatic Animal Disease Reporting (QAAD) system 8, established since 1998 under an FAO regional Technical Cooperation Programme, participated by 21 countries in Asia, where results from both active and passive surveillance systems are reported. Most countries have now reached level II. 8 EFSA Journal 2011;9(10):195 7

8 Current situation in Australia, South East Asia and other parts of the world A decrease of severity in outbreaks has been observed in infected countries which may be speculated to be the result of a reduction in numbers of fish of the susceptible species, although confirmation of this hypothesis does not exist. In Asia, there were reports of reduction in production from aquaculture (Subasinghe, 1997) and catches or landings from capture fisheries during serious EUS outbreaks (Das, 1994; Callinan et al., 1999). EUS is not the only case of a pathogenic fungus having negative impact on biodiversity; another aquatic fungal pathogen, Aphanomyces astaci Schikora, 1906, devastated the European crayfish populations (OIE, 2009). In Asia annual reoccurrence of the disease in the wild has been seen but the pattern of occurrence is not the same in all countries. Risk factors for disease occurrence seem also to vary between regions for example rainfall in Asia or type of soil (and release of H2SO4 and ph drop) in Australia. The opinion of the experts at the meeting was that it is extremely difficult for a country where outbreaks have occurred in the wild to regain free status. According to FVO the demonstration and maintenance of freedom from EUS may be feasible at compartment level but not at a country level. Many countries in Asia have some form of passive surveillance for EUS as part of NACA s quarterly aquatic animal disease reporting systems. Surveys to demonstrate freedom of A invadans are being conducted in Singapore Thailand and India. The surveys are limited to farms producing ornamental fish for export to the EU and no positive fish have been found. However it was confirmed by the participants at the meeting that often the fish origin is different than the one described in the health certificate accompanying consignments. Large numbers of fish are gathered and sold from Singapore. Such practice could explain the report in Hanjavanit et al. (1997) of EUS detection in fish imported to Japan from Singapore and the absence of any other reports in the country. The majority of world wide EUS reports involve wild fish, which does not necessarily imply that farms are also infected. At the moment, health certificates for ornamental fish destined for closed ornamental facilities, do not have information on origin with regards to farmed or wild. Only a few species traded are of both wild and captive origin, several species of sharks (e.g. Epalzeorhynchus, Garra). Some species such as Discus fish, tetra's, Corydoras are collected in the wild in South America but captive bred in Asia Significance of the recent Canada outbreak Canada experienced a first outbreak in September This event was not associated with a visible die-off of finfish. Confirmation of the infection by A. invadans was obtained by PCR and histological evaluation of clinically affected fish 9. There is no information to evaluate the infection persistence in the region Introduction pathway investigations in historic outbreaks? There are no comprehensive published studies on sources of introduction for EUS in areas where it was previously exotic. According to the experts and given the history of other disease introductions, it is likely that the pathogen is introduced with infected fish possibly with subclinically infected fish, or carriers. In this context, crayfish plague caused by Aphanomyces astaci was mentioned. Aphanomyces astaci, which is very closely related to A. invadans, causes disease in European crayfish species and was spread across Europe through North American crayfish, which act as healthy carriers. Therefore, it was suggested that A. invadans may also use fish (or possibly other aquatic organisms) as carriers. 9 EFSA Journal 2011;9(10):195 8

9 The FAO representative mentioned her experience from spread of EUS to remote islands of the Philippines, which seemed most likely to be associated with movement of infected, but clinically healthy fish Other information sources about EUS infected areas? Quarterly reports on the disease status with regards to various OIE notifiable diseases including EUS are available on the NACA website 10 According to OFI there have been no reports of EUS on ornamental facilities. A large number of publications are available in the literature which provide information on EUS infected areas Actions taken in infected countries? Have trade/movement restrictions being taken? A ban on fishing was imposed during the African outbreak in Current trade practices and trade volumes of Ornamental fish How are suppliers of ornamental fish evaluated? There is no standard for evaluation of suppliers. Large wholesalers usually demand high quality of fish from their suppliers while smaller importers (retailers) tend to pay lower prices and be less demanding. Also the higher the species value, the higher the quality of the fish. The ornamental trade industry is extremely varied in terms of volume and standards applied. The most common practice is that losses due to dead fish on transport are taken by the exporter, while transport costs (often larger than the fish value) are taken by the importer. Mortalities above 2-3% upon arrival of the fish in the importing country, would lead to complaints by the importer to the supplier. If this was a repeated occurrence, the importer would cease to source fish from this supplier Are there significant differences between how trade (import and internal distribution) is done in different countries? Trade of ornamental fish including importation and distribution within Europe is extremely complex with numerous steps involved in the process. Regarding import, there are three main types of importers: consolidators (or transhippers), wholesalers and retailers. Consolidators will take orders from customers and arrange the logistics of import and distribution with fish delivered direct to retail. There is little application for biosecurity for this business type, as boxes are on the whole not opened. Although they are common in UK, in Germany transhipping is only allowed if there are facilities to store fish. In Holland transhipping will be forbidden from At the level of wholesaler and retailer the differences observed are mainly at the enterprise level than at country level Trade volumes Sources of information regarding trade volumes are: EUROSTAT, TRACES and FAO. Several deficiencies were noted and discussed regarding the data available by these systems. The biggest problem is the lack of data concerning the species imported. TRACES has very limited provisions to capture species information, for species susceptible to EUS. Although this information is available on packing lists of consignments, it is often incorrect. OFI has published 2 books with standard common and scientific names to address the problem. It was also recognised that it is very difficult or even 10 hp EFSA Journal 2011;9(10):195 9

10 impossible for the official veterinarians (OV) at the Border inspection posts (BIP) to accurately identify the species imported as EUS susceptible or not. OFI is at the moment trying to organise a volunteer scheme for their members to declare the numbers and species of imported ornamental fish. FEAP does not have any data collection regarding ornamental fish, not even for the fish produced in the EU. Intra community trade of ornamental fish is not documented. According to OFI, significant trade occurs between EU MS. Prior to its adhesion to the EU, the Czech Republic was one of the largest exporters of ornamental fish into the EU Quarantine, is it happening, for how long, which species and how? Commission Decision 2008/ establishes minimum requirements for quarantine facilities. OFI expressed the concern that these requirements are extremely difficult or even impossible to apply in commercial practice. It was noted that there is no publicly available European registry of quarantine facilities. Wild caught fish intended for use in aquaculture within a respective EU MS are usually placed in quarantine. Licences are issues by local competent authorities Are there any open ornamental facilities registered in the EU? The only open ornamental facilities (as defined by Council Directive/2006/88/EC 12 ) are authorised in the UK. This applies to businesses who import cold water ornamental fish Are we aware of a EU registry of closed ornamental facilities? The CD 2006/88/EC does not establish requirements for either registration or authorization of closed ornamental facilities. Commercial activities are licensed at national or local level and it is not known if the competent authorities for aquatic health in the member states have such registry. In the UK, only importers are authorised. Some countries have registers of retailers in order to effectuate controls for animal welfare conditions. OFI has about 190 members from some 45 countries 13. Members can be companies, institutions or bodies who are actively involved in the Ornamental Aquatic Industry, such as importers, wholesalers, producers of ornamental aquatic species and also some countries aquatic health competent authorities. The association has a Code of Ethics 14, which mainly focuses on honest trade and a voluntary Code of Conduct 15, which focuses on good husbandry practices. Within the EU, ornamental fish businesses are often members of pet trade organisations. The UK has an organisation that is specifically dedicated to the ornamental fish trade (OATA). Members include importers and retailers Pathways for introduction The WG has described pathways for the introduction of A. invadans via introduction of live fish from thirds countries. Live fish (ornamental and non ornamental) will enter the community through one of /946/EC: Commission Decision of 12 December 2008 implementing Council Directive 2006/88/EC as regards requirements for quarantine of aquaculture animals (notified under document number C(2008) 7905) (Text with EEA relevance) OJ L 337, , p Council Directive 2006/88/EC of 24 October 2006 on animal health requirements for aquaculture animals and products thereof, and on the prevention and control of certain diseases in aquatic animals. OJL 328, , p EFSA Journal 2011;9(10):195 10

11 the approved BIPs. The endpoint of the import assessment was the first EU aquaculture facility reached by the imported live fish. According to EU legislation three types of facilities are defined: farm (F), open ornamental facilities (OOF) and closed ornamental facilities (COF). The individual hobbyist is excluded from the scope of the directive. Taking into account this pathway the risk of introduction was linked with the probability of infection and the volume of fish imported. The certification of EUS freedom by exporters and the capacity for detection of infection at the BIP are essential to prevent introduction. The participants agreed on the general assumptions of the WG Sensitivity of overall surveillance system in infected countries The capacity for diagnosing EUS, varies substantially in infected countries. To capture the various levels of diagnostic capacity, NACA quarterly reports on aquatic animal disease situation in member countries, include information regarding the diagnostic methods employed (see section ). A problem highlighted by an EFSA representative was that information on the level or type of surveillance (and therefore evidence for absence, if EUS was not reported) in various countries is usually absent (for example the OIE WAHID website 16 ). The FVO representative commented that the surveillance programmes for aquatic animal diseases in many South East Asian countries would currently not be considered sufficient to demonstrate freedom from infection. The sampling was not comprehensive, there were traceability issues with the animals brought into ornamental fish facilities, and the water supply to such facilities was often using surface water, which meant that there was possibly no or little control with regards to exposure via water (see FVO reports). Several Asian countries lack registries of their ornamental fish farms and businesses (e.g. businesses capturing wild fish). Often the clinical manifestation of EUS depends on the presence of risk factors. Large scale outbreaks require the presence of these risk factors. If active surveillance, including sampling, is undertaken while no clinical disease is apparent, detection is unlikely. It was also mentioned that if clinical signs consistent with EUS (e.g. skin ulcers, skin lesions) were observed in ornamental fish, the most likely suspicion would be of bacterial infection. Fish would be treated using antibiotics and either recover or die. Therefore, clinical EUS may be overlooked Detection of EUS at the Border Inspection Point The species names are not always included in the health certificate or even in the packing list since the exporter may not be up to date with current species names and may specify them incorrectly. It can be difficult to identify which species of fish are arriving at the BIP, as they may be young/too small to differentiate between species and furthermore, they are transported in dark conditions. Inspection at BIP comprises a documentation check and visual inspection of a sample of the boxes/consignments. The time available for inspection is scarce and the large numbers of consignments /boxes in some of the EU BIPs do not allow for a thorough examination. Furthermore, training on aquatic animal taxonomy and health is usually not requested from OV Controls at wholesaler facilities Wholesalers are subject to the rules applicable to COF. No specific rules for wholesalers are laid down in the EU legislation Release assessment The EFSA mandate was to consider the risk of release of A. invadans, in particular from infected COF). The release of ornamental fish into the wild or to OOF, or farms is illegal (the assumption of 16 EFSA Journal 2011;9(10):195 11

12 full compliance was taken for this assessment). Live fish from COF are sold mainly to hobbyists, this category is excluded from the scope of EU legislation concerning Aquatic Animal Health, but it is known to establish a link to natural waters either by live fish release or disposal of dead fish. The definition of closed facilities includes the treatment of effluents; generally water discarded by such facilities is discarded into urban sewage systems. There is some uncertainty about the efficacy of the treatment for the elimination of fungal spores. Importers often treat the fish on arrival with salt (mainly cold freshwater fish) in order to control parasites and increase the production of skin mucus that might have become damaged during transport. For freshwater fish, saltwater dips at a concentration of 3 for 30 seconds to 30 minutes, are recommended (OFI, 2007). There is some uncertainty about the efficacy of the treatment for the elimination of fungal spores and hyphae. A. invadans has been shown to sporulate at 2, but not at 4 NaCl (Fraser et al. 1992). Transport water may be complemented with substances lowering N values in tranport water. Some exporters use acridine dyes. The effect of these substances on Aphanomyces invadans is not clear. More information would be required Spread and persistence The spread and persistence of A. invadans once introduced in the EU, was the third TOR addressed by EFSA. The likelihood of introduction of A. invadans into the EU and subsequent release is in apparent contradiction with the long-term no reporting of EUS in EU. The WG hypothesised 4 scenarios to explain the apparent contradiction: 1. Fish in European waters have never been exposed to A. invadans. 2. EUS does not establish but fades out after introduction due to unfavourable conditions. 3. EUS epidemics repeatedly establish and spread unnoticed in EU because certain conditions (e.g. temperature or species susceptibility) prevent disease expression. 4. EUS is already endemic in EU and is regularly misdiagnosed What is the potential that EUS could be unrecognised? EUS has not really been a subject for the aquaculture industry to date. The level of awareness of farmers with the clinical presentation of the disease may be limited. In extensive production systems, such as Carp farming in Europe, fish would not be inspected on a daily basis. Sometimes fish are not assessed for 12 months. After 12 months, 30% may have been lost. This would not be unusual and the reasons for the losses are not often investigated, but considered normal. High numbers of dead fish in the wild might go unnoticed due to poor monitoring. If large numbers of dead fish are found, it is normally presumed firstly to be from a pollution incident. Sample quality to diagnose EUS or other aquatic animal diseases is often limited (e.g. shipped to laboratory frozen, only dead fish sampled, fish often degraded).it would be useful to have access to national data, to at least establish proportion of fish kills not considered to be attributable to pollutants. Since EUS was listed in the Annex IV of the CD/2006/88/EC as an exotic disease, the MS have the obligation of nominating their own national reference laboratory, or one from another MS to proceed to necessary laboratorial exams, in case of EUS suspicion. The Community reference laboratory has initiated a series of activities in order to increase awareness to the disease and improve diagnostic capacity in Europe. The first proficiency test is being performed this year (2011) and results are expected soon. The participants of the meeting were not aware of any survey being conducted in Europe to demonstrate absence or presence of the disease/infection. The participants were not aware of any monitoring program for EUS focusing on ornamental fish. However, the FLI plans to test ornamental fish provided through the ornamental fish importers in Germany. The FLI has been granted derogation for reporting EUS, if it was detected. EFSA Journal 2011;9(10):195 12

13 What are the chances to detect EUS clinically? The disease could be mistaken for bacterial or a physical injury. Laboratory diagnostic procedures would not routinely be employed. Fish suspected of bacterial infection would be treated using antibiotics; fish would either recover or die. Even where lab diagnostic methods are used, these would often not include sampling skin ulcers or other skin lesions. Therefore, clinical EUS may be overlooked. See also section Is the aquaculture industry taking measures to protect farms against EUS introduction? Awareness for this disease between aquaculture producers is believed to be very low. The opinion of the participants at the meeting is that risk of spread into aquaculture facilities is higher through contaminated water (than live fish movements into farms) since the majority of freshwater farms do not have inlet water treatment. Disease dissemination could also occur by ichthyophagous birds, especially in wetlands (extensive farms) or areas with particularly high concentration of farms. However, it is believed that if the pathogen is present in the natural water bodies, the amount of pathogen is probably too low to cause infection and disease in farmed fish Impact What preparation was undertaken by the ornamental fish industry for the implementation of the Directive concerning EUS? OFI is promoting a series of missions in exporting countries, in order to make producers aware of European requirements and the need to establish free of disease farms/compartments. Surveys to demonstrate freedom of A. invadans are being conducted in Singapore and Thailand. India is also considering establishing a surveillance program. The surveys are limited to farms producing ornamental fish for export to the community and no positive fish have been found. OFI mentioned that ornamental fish farms are often small scale enterprises, which may not be able to afford biosecurity measures that may be required to fulfil conditions for compartment status Are there any studies on the possible impact of EUS to EU aquaculture? Although no studies are available regarding possible EUS impact to EU aquaculture, the participants at the meeting expressed their concerns since some other diseases such as Koi Herpesvirus (KHV) believed to have been introduced with ornamental fish had considerable impact to the EU aquaculture What would it mean for EU aquaculture if the EU or one of its member states was no longer EUS free? Aquaculture farmers are more concerned with the cost of surveillance than the actual possible impact on their fish stocks. In the majority of EU MS, farmers contribute to surveillance costs and surveillance for any additional disease might be a problem. Extensive aquaculture is more likely to be affected by EUS, since stocks would not be closely monitored and losses may not be noticed until a late stage Trends in aquaculture cultured species? The majority of the fish species produced by EU aquaculture are not known to be highly susceptible to EUS. European catfish (Silurus glanis), trout (Oncorhynchus mykiss) and Common carp (Cyprinus carpio) have been experimentally infected. Channel catfish, (Ictalurus punctatus), black bullhead (Ameiurus melas) and african catfish (Clarias gariepinus) are naturally infected. EFSA Journal 2011;9(10):195 13

14 Rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio) are widely farmed in Europe; european catfish (Silurus glanis) is farmed mainly in Austria, Hungary, Poland and the Czech Republic (production in the last years was between 600 and 1,000 tons/year). Channel catfish (Ictalurus punctatus) is farmed in East Europe and Italy, mainly in open farms (production in Italy for 2010 estimated in 300 tons). Black bullhead (Ameiurus melas formerly Ictalurus melas), a species which is very close to brown bullhead (Ictalurus nebulosus), is farmed in Italy in open farms (production in Italy for 2010 estimated in 250 tons). Channel Catfish (Clarias spp.) is mainly farmed in Poland, Hungary, Netherlands and Belgium (estimated production in EU for 2010 was over 6,500 tons); the main producer is Netherlands (more than 3,500 tons, but production is decreasing); in Netherlands and Belgium it is farmed only in closed recirculation systems, in Hungary and Poland mainly in semi-intensive basins. Grey mullet (Mugil cephalus), the main farmed species in EU, is concentrated in the Mediterranean area (Italy and Greece), its expansion is limited because it depends mainly on wild fry. Mullets are mainly farmed in extensive or semi-intensive farms (lagoons, estuarine brackish wet lands). It is not always easy to distinguish if the productions are derived from fish farming or fishing (especially in lagoons). Furthermore, there is considerable seasonal variation. In Italy, API (Associazione Piscicoltori Italiani - Italian Fish Farmers Association) estimates an annual production (with reference to the last 5 years) ranging between and tons for Mugil cephalus and other mullets: Chelon labrosus, Liza aurata, L saliens, L ramada. Another issue to be considered is the production of marine species such as seabream (Sparus aurata) and seabass (Dicentrarchus labrax) in water of low salinity which may be appropriate for the survival of A. invadans. EFSA Journal 2011;9(10):195 14

15 REFERENCES Bondad-Reantaso MG, McGladdery, SE, East I, and Subasinghe RP, (eds.) Asia Diagnostic Guide to Aquatic Animal Diseases. FAO Fisheries Technical Paper No. 402, Supplement 2. Rome, FAO p. Callinan RB, Chinabut S, Mohan CV and Lilley JH, Report of EUS Extension Visits to Nepal, India and Sri Lanka June Australian Centre for International Agricultural Research and Department for International Development, 32 p. Das MK, Outbreak of the fish disease, epizootic ulcerative syndrome in India - an overview. p In: R.J. Roberts, B. Campbell and I.H. MacRae. (eds.) Proceedings of the ODA Regional Seminar on Epizootic Ulcerative Syndrome, January, Aquatic Animal Health Research Institute, Bangkok. EFSA, Scientific Opinion of the Panel on AHAW on a request from the European Commission on aquatic animal species susceptible to diseases listed in the Council Directive 2006/88/EC. The EFSA Journal 808, FAO, Report of the International Emergency Disease Investigation Task Force on a Serious Finfish Disease in Southern Africa, May Food and Agriculture Organization of the United Nations, Rome, p. 70. FAO, Report of the expert consultation on ulcerative fish diseases in the Asia-Pacific region. (TCP/RAS/4508). Bangkok, August Food and Agriculture Organization of the United Nations, Regional Office for Asia and the Pacific, Bangkok. Fossa SA, Bassleer GMO, Chuan LL and Ploeg A, OFI Educational publication 2: International transport of Live Fish in the Ornamental aquatic Industry. Ornamental Fish International, 126pp. Fraser GC, Callinan RB and Calder LM, Aphanomyces Aphanomyces species associated with red spot disease: an ulcerative disease of estuarine fish from eastern Australia. J. Fish Dis., 15, Hanjavanit C, Suda H, and Hatai K, Mycotic granulomatosis found in two species of ornamental fishes imported from Singapore. Mycoscience 38, Subasinghe R, South Asia. In: Review of the State of World Aquaculture. FAO Fish. Circ. No. 886, Rev. 1 (Chap ). [WWW document] URL: World Organisation for Animal Health OIE, Manual of Diagnostic Tests for Aquatic Animals, OIE, Paris, available at EFSA Journal 2011;9(10):195 15

16 ABBREVIATIONS AHAW Animal Health and Welfare API Associazione Piscicoltori Italiani BIP Border inspection post CA Competent authority COF Closed ornamental facility CRL Fish Diseases Community Reference Laboratory CVED Common veterinary entry document EC European Commission EU European Union EUROSTAT Statistical Office of the European Union EUS Epizootic ulcerative syndrome F Farm FAO Food and Agriculture Organization FEAP Federation of European Aquaculture Producers FLI Federal Institute of Animal Health FVO Food and Veterinary Office IRA Import Risk Assessment KHV Koi Herpes Virus MS(s) Member State(s) NACA Network of Aquaculture Centres in Asia-Pacific NRL National Reference Laboratory OATA Organismo Assistenza Tecnica Agricola OFI Ornamental Fish International OIE World Organisation for Animal Health OOF Open Ornamental Facility OOF Open ornamental facility OV Official veterinarian PCR Polymerase chain reaction RA Risk Assessment SS Susceptible species SVC Spring Viraemia of Carp TOR Terms of Reference TRACES Trade Control and Export System WAHID World Animal Health Information Database WG Working Group EFSA Journal 2011;9(10):195 16