Commission Delegated Regulation (EU) 2020/689 of 17 December 2019 supplementing Regulation (EU) 2016/429 of the European Parliament and of the Council as regards rules for surveillance, eradication programmes, and disease-free status for certain listed and emerging diseases (Text with EEA relevance) (Text with EEA relevance)

• (a) it must take into account factors influencing the risks for the spread of infection with Bonamia ostreae including other establishments and wild molluscs, such as:
• (i) the number, age, rate and distribution of the mortalities of molluscs on the establishment or group of establishments infected with Bonamia ostreae;
• (ii) the distance to and density of neighbouring establishments or groups of establishments and wild molluscs;
• (iii) the proximity to processing establishments, contact establishments or groups of establishments;
• (iv) the species, especially susceptible species and vector species, present at the establishments or groups of establishments;
• (v) the farming practices applied in the affected and neighbouring establishments and groups of establishments;
• (vi) the hydrodynamic conditions; and
• (vii) other factors of epidemiological significance identified;

• (b) the geographical demarcation must comply with the following minimum requirements:
• (i) the protection zone must consist of an area included in a circle with a radius of at least one tidal excursion or at least 5 km, whichever is larger, centred on the establishment infected with Bonamia ostreae, or an equivalent area determined according to appropriate hydrodynamic or epidemiological data; and
• (ii) the surveillance zone must consist of an area surrounding the protection zone, of overlapping tidal excursion zones; or an area surrounding the protection zone and included in a circle of radius 10km from the centre of the protection zone; or an equivalent area determined according to appropriate hydrodynamic or epidemiological data; or
• (iii) where separate protection and surveillance zones are not established, the restricted zone must consist of an area comprising both the protection zone and the surveillance zone.

Table 5.A

Scheme for Member States, zones or compartments for the 3-year control period which precedes the achievement of status free from infection with Bonamia ostreae

Year of surveillance	Number of health visits per year to each establishment or group of establishments	Number of laboratory examinations per year	Number of molluscs in the sample
Year 1	1	1	150
Year 2	1	1	150
Year 3	1	1	150

Section 4

Maintenance of status free from infection with Bonamia ostreae

• 1.When targeted surveillance is required in order to maintain the status free from infection with Bonamia ostreae of a Member State, a zone or a compartment, in accordance with Article 81, all establishments keeping listed species within the Member State, zone or compartment concerned must be subject to health visits and molluscs must be sampled in accordance with Table 5.B, taking into account the risk level of the establishment for the contraction of infection with Bonamia ostreae.

• 2.When determining the frequency of health visits required to maintain the status free from infection with Bonamia ostreae of compartments where the health status regarding that disease is dependent on the health status of the aquatic animal populations in surrounding natural waters, the risk for the contraction of infection with Bonamia ostreae must be regarded as high.

• 3.The status free from infection with Bonamia ostreae may only be maintained as long as all samples, using the diagnostic methods set out in point 2 of Section 5 have produced negative results for Bonamia ostreae and any suspicion of infection with Bonamia ostreae has been ruled out in accordance with the diagnostic methods set out in point 3 of Section 5.

Table 5.B

Scheme for Member States, zones or compartments to maintain status free from infection with Bonamia ostreae

Risk level [^E0030]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of molluscs in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 3 years	1 every 3 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I other than in the case of dependent compartments where all establishments are deemed to be high risk.

Section 5

Diagnostic and sampling methods

• 1.The whole animal must be submitted to the laboratory for the performance of the diagnostic tests provided for in points 2 and 3.

• 2.The diagnostic methods to be used to grant or maintain status free from infection with Bonamia ostreae, in accordance with Sections 2 to 4 must follow the detailed diagnostic methods and procedures approved by the EURL for Mollusc Diseases and must be histopathology, tissue imprints or PCR.

• 3.When a suspicion of infection with Bonamia ostreae is required to be confirmed or ruled out in accordance with Article 58, the following visit, sampling and testing procedure must be complied with:

• (a) the investigation must include at least one sampling of 30 molluscs of susceptible species if the suspicion is based on a mortality report, or if not, 150 molluscs of susceptible species after the beginning of the transmission period of Bonamia ostreae. When the transmission period is not known, the sampling shall begin in the winter or at the beginning of spring;

• (b) the samples must be tested using the diagnostic methods set out in point (i) following the detailed diagnostic methods and procedures which have been approved by the EURL for Mollusc Diseases:
• (i) the presence of Bonamia ostreae must be considered as confirmed when a positive result by histopathology, tissue imprints or in situ hybridisation is combined with a positive result by PCR followed by sequencing. If biological material is not available for histopathology, tissue imprints or in situ hybridisation, the presence of Bonamia ostreae must be considered as confirmed when positive results are obtained using two PCR assays targeting different fragments of the parasite genome and completed by sequencing;
• (ii) the suspicion of the presence of infection with Bonamia ostreae must be ruled out, if those tests reveal no further evidence of the presence of Bonamia ostreae.

CHAPTER 6

Eradication, disease-free status and diagnostic methods for infection with white spot syndrome virus (WSSV)

Section 1

General requirements for health visits and sampling

Health visits and sampling for the surveillance referred to in Article 3(2)(b)(ii) and (iii) must comply with the following requirements:

• (a) the sampling of crustaceans for laboratory examination must be carried out whenever the water temperature is likely to reach its highest annual point. That requirement concerning water temperature must also apply to health visits where these are feasible;

• (b) when farmed crustaceans must be sampled in accordance with the requirements set out in Sections 2 to 4, the following criteria must apply:
• (i) if weak or moribund crustaceans are present in the production units, such crustaceans must primarily be selected. If such crustaceans are not present, those selected must include crustaceans of different size cohorts namely juveniles and adults of the selected susceptible species, proportionally represented in the sample;
• (ii) if more than one water source is utilised for crustacean production, susceptible crustaceans representing all water sources must be included for sampling;

• (c) when targeted surveillance in wild populations is required due to the small number of establishments covered by the eradication programme, the number and geographical distribution of the sampling points must be determined to obtain a reasonable coverage of the Member State, zone or compartment. The sampling points must also be representative of the different ecosystems where the wild populations of susceptible species are located namely marine, estuary, river and lake systems. In such situations, the crustaceans to be sampled must be selected as follows:
• (i) in marine and estuary systems areas, one or more of the following species must be selected: Carcinus maenas, Cancer pagurus, Eriocheir sinensis, Liocarcinus depurator, Liocarcinus puber, Crangon crangon, Homarus gammarus, Palaemon adspersus or penaeid shrimp species namely Penaeus japonicus, Penaeus kerathurus, Penaeus semisulcatus. If those species are not present, the sample must be representative of other susceptible decapod species present;
• (ii) in river and lake systems, one or more of the following species must be selected: Pacifastacus leniusculus, Astacus leptodactylus, Austropotamobius pallipes or Orconectes limosus. If those species are not present, the sample must be representative of other susceptible decapod species present;
• (iii) if weak or moribund crustaceans are present, such crustaceans must primarily be selected. If such crustaceans are not present, those selected must include crustaceans of different size cohorts namely juveniles and adults of the selected susceptible species, proportionally represented in the sample.

Section 2

Granting of the status free from infection with WSSV in Member States, zones and compartments of unknown health status

• 1.The status free from infection with WSSV may only be granted to a Member State, a zone or a compartment with an unknown health status with regard to infection with WSSV if all establishments or groups of establishments keeping listed species within the Member State, zone or compartment and where required, sampling points in wild populations, have been subject to the following 2-year scheme:

• (a) the establishments or groups of establishments have been subject to health visits and sampled for a minimum period of 2 consecutive years as laid down in Table 6.A;

• (b) during that 2-year period, the testing of all samples using the diagnostic methods set out in point 2 of Section 5 have produced negative results for infection with WSSV and any suspicion of infection with WSSV has been ruled out in accordance with the diagnostic methods set out in point 3 of Section 5;

• 2.If infection with WSSV is detected during the 2-year scheme referred to in point 1, before starting a new 2-year scheme, relevant establishments in the Member State, zone or compartment must:

• (a) be subject to the minimum disease control measures laid down in Articles 58 to 65;

• (b) be repopulated with crustaceans from an establishment in a Member State, zone or compartment free from infection with WSSV or from an establishment in a Member State, zone or compartment covered by an eradication programme for that disease.

Section 3

Granting of the status free from infection with WSSV in Member States, zones and compartments known to be infected with WSSV

• 1.The status free from infection with WSSV may only be granted to a Member State, a zone or a compartment known to be infected with WSSV if all establishments keeping listed species within that Member State, zone or compartment have been subject to an eradication programme that complies with the following requirements:

• (a) the minimum control measures laid down in Articles 55 to 65 must have been effectively applied, and a restricted zone of an appropriate size as provided for in point (c) of Article 58(1), where appropriate, divided into a protection zone and surveillance zone; must have been established in the vicinity of the establishment(s) declared infected with WSSV taking into account the requirements set out in point 2;

• (b) all establishments keeping listed species within the protection zone, or where a protection zone has not been established, the restricted zone, not infected with WSSV must be subject to an investigation comprising at least the following:
• (i) the collection of samples for testing of 10 crustaceans, when clinical signs or post-mortem lesions consistent with infection WSSV are observed, or 150 crustaceans, when clinical signs or post-mortem lesions are not observed; and
• (ii) health visits; in those establishments where the tests referred to in (i) have produced negative results, health visits must continue once per month during the season when the water temperature is likely to reach its highest annual points, until the protection zone has been withdrawn in accordance with point (c);

• (c) relevant establishments must be emptied in accordance with Articles 62, cleaned disinfected in accordance with Article 63 and fallowed in accordance with Article 64. The duration of the fallowing period must be at least 6 weeks. When all infected establishments are emptied, at least 3 weeks of synchronous fallowing shall be carried out. When fallowing of the officially declared infected establishments is carried out, the protection zones shall be converted into surveillance zones;

• (d) repopulation may only take place when all infected establishments have been emptied, cleaned, disinfected and fallowed in accordance with point (c);

• (e) all establishments other than those referred to in point (f) which keep listed species within the Member State, zone or compartment covered by the eradication programme and, when surveillance in wild populations is required, all sampling points selected to provide the greatest coverage of the geographical area included in the eradication programme must be subject at least to the scheme set out in Section 2;

• (f) an individual establishment which keeps listed species and which has a health status which is independent of the health status of the surrounding waters is not required to comply with the scheme set out in Section 2 following a disease outbreak provided the establishment complies with the requirements set out in paragraph 3 of Article 80 and is repopulated with crustaceans sourced from Member States, zones or compartments with status free from infection with WSSV.

• 2.The restricted zone must have been defined on a case-by-case basis taking into account factors influencing the risks for the spread of WSSV to farmed and wild crustaceans, such as:

• (i) the number, age, rate and distribution of the mortalities of crustaceans on the establishment or group of establishments infected with WSSV including other establishments and wild crustaceans;

• (ii) the distance to and density of neighbouring establishments or groups of establishments including wild crustaceans;

• (iii) the proximity to processing establishments, contact establishments or groups of establishments;

• (iv) the species, especially susceptible species and vector species, present at the establishments or groups of establishments;

• (v) the farming practices applied in the affected and neighbouring establishments and groups of establishments;

• (vi) the hydrodynamic conditions; and

• (vii) other factors of epidemiological significance identified.

Table 6. A

Scheme for Member States, zones and compartments for the 2-year control period which precedes the achievement of status free from infection with WSSV

Year of surveillance	Number of health visits per year to each establishment or group of establishments	Number of laboratory examinations per year	Number of crustaceans in the sample
Year 1	1	1	150
Year 2	1	1	150

Section 4

Maintenance of status free from infection with WSSV

• 1.When targeted surveillance is required in order to maintain the status free from infection with WSSV of a Member State, a zone or a compartment, in accordance with Article 81, all establishments keeping listed species within the Member State, zone or compartment concerned must be subject to health visits and crustaceans must be sampled in accordance with Table 6.B, taking into account the risk level of the establishment for the contraction of infection with WSSV.

• 2.In Member States, zones or compartments where the number of establishments is limited and targeted surveillance in those establishments does not provide sufficient epidemiological data, the surveillance to maintain disease-free status must include sampling points selected in accordance with the requirements laid down in point (b) of Section 1.

• 3.When determining the frequency of health visits required to maintain the status free from infection with WSSV of compartments where the health status regarding that disease is dependent on the health status of the aquatic animal populations in surrounding natural waters, the risk for the contraction of infection with WSSV must be regarded as high.

• 4.The status free from infection with WSSV may only be maintained as long as all samples, using the diagnostic methods set out in point 2 of Section 5 have produced negative results for WSSV and any suspicion of infection with WSSV has been ruled out in accordance with the diagnostic methods set out in point 3 of Section 5.

Table 6. B

Scheme for Member States, zones or compartments to maintain status free from infection WSSV

Risk level [^E0031]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of crustaceans in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 2 years	1 every 4 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I other than in the case of dependent compartments where all establishments are deemed to be high risk.

Section 5

Diagnostic and sampling methods

• 1.Samples of integumental epidermis, either dissected or contained within walking legs, pleopods, mouthparts or gills of the test animal must be fixed in 95 % ethanol prior to the preparation of samples for PCR.

• Other samples, fixed for histology and transmission electron microscopy may be collected to support diagnostic data arising from PCR.

• 2.The diagnostic method and procedures to be used to grant or to maintain disease-free status with regard to infection with WSSV must be PCR followed by sequencing. When applying these diagnostic methods, the corresponding detailed methods and procedures which have been approved by the EURL for Crustacean Diseases must be followed.

• In the case of a positive result from the PCR test, the result must be followed by sequencing of the amplicon before the initial control measures provided for in Article 63 of Regulation (EU) 2016/429 are implemented.

• 3.When a suspicion of infection with WSSV is required to be confirmed or ruled out in accordance with Article 58, the following visit, sampling and testing procedure must be complied with:

• (a) the investigation must include at least one health visit and one sampling of 10 crustaceans when clinical signs or post-mortem lesions consistent with infection with WSSV are observed or 150 crustaceans when clinical signs or post-mortem lesions are not observed. The samples must be tested using the diagnostic method set out in point 2;

• (b) the presence of WSSV must be considered as confirmed when PCR followed by sequencing, carried out in accordance with the detailed methods and procedures which have been approved by the EURL for Crustacean Diseases test positive for WSSV. The suspicion of infection with WSSV may be ruled out, if those tests reveal no further evidence of the presence of the virus.

PART III

REQUIREMENTS FOR DEMONSTRATING THE IMPLEMENTATION OF SURVEILLANCE PROGRAMMES FOR CATEGORY C DISEASES AND FOR RESTARTING THOSE PROGRAMMES AFTER A DISEASE OUTBREAK

Part III covers the requirements for establishments to demonstrate the implementation of a surveillance programme for a particular disease and the requirements to restart that surveillance programme following a disease outbreak.

Viral haemorrhagic septicaemia (VHS)	Chapter 1
Infectious haematopoietic necrosis (IHN)	Chapter 1
Infection with HPR-deleted infectious salmon anaemia virus	Chapter 2
Infection with Marteilia refringens	Chapter 3
Infection with Bonamia exitiosa	Chapter 4
Infection with Bonamia ostreae	Chapter 5
Infection with white spot syndrome virus (WSSV)	Chapter 6

CHAPTER 1

Requirements for establishments to demonstrate the implementation of a surveillance programme for VHS or IHN and requirements to re-start that programme following a disease outbreak

Section 1

General requirements for health visits and sampling for VHS and IHN

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) health visits and sampling must be carried out during the period of the year when the water temperature is below 14 °C or when temperatures below 14 °C are not reached, samples must be taken at the lowest annual points;

• (b) all production units, such as ponds, tanks and net cages, must be examined for the presence of dead, weak or abnormally behaving fish. Particular attention must be paid to the water outlet area where weak fish tend to accumulate because of the water current;

• (c) fish of listed species to be collected as samples must be selected as follows:
• (i) if rainbow trout are present, only fish of that species must be selected for sampling, except where other susceptible species are present which show typical signs of VHS or IHN; if rainbow trout are not present, the sample must be representative of all other susceptible species which are present;
• (ii) if weak, abnormally behaving or freshly dead but not decomposed fish are present, such fish must be selected; if more than one water source is utilised for fish production, fish representing all water sources must be included in the sample;
• (iii) the fish selected must include fish collected in such a way that all parts of the establishment, as well as all year classes, are proportionally represented in the sample.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits must be carried out and fish must be sampled in accordance with Section 1 and Table 1.

• 2.Samples which are collected in accordance with Section 1 and Table 1 must be tested using the diagnostic methods set out in point 2 of Section 5 of Chapter 1 of Part II and produce negative results for VHS or IHN.

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with VHS or IHN, may restart a surveillance programme for these diseases provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using fish that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from VHS or IHN;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for VHS or IHN; or
• (iii) implementing a surveillance programme for VHS or IHN.

Table 1

Surveillance programme for VHS/IHN

Risk level [^E0032]	Number of health visits per year to each establishment	Number of fish in the sample [^E0033]
High	1 every year	30
Medium	1 every 2 years	30
Low	1 every 3 years	30

In the case of coastal zones or coastal compartments, the samples must be collected no sooner than 3 weeks after the transfer of the fish from fresh to saltwater.

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I. Maximum number of fish per pool: 10

CHAPTER 2

Requirements for establishments to demonstrate the implementation of a surveillance programme for HPR-deleted ISAV and to re-start that programme after a disease outbreak

Section 1

General requirements for health visits and sampling for infection with HPR-deleted ISAV

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) health visits and sampling must take into account all production units, such as ponds, tanks and net cages, to determine if dead, weak or abnormally behaving fish are present. Particular attention must be paid to the edge of cages or the water outlet area as relevant, where weak fish tend to accumulate because of the water current;

• (b) the fish to be collected as samples must be selected as follows:
• (i) only moribund or freshly dead but not decomposed fish must be selected; in particular fish demonstrating anaemia, bleeding or other clinical signs suggesting circulatory disturbances must be prioritised for collection;
• (ii) if Atlantic salmon are present, only fish of that species must be selected for sampling, except where other susceptible species are present which show typical signs of ISA. If there are no Atlantic salmon in the establishment, other listed species must be sampled;
• (iii) if more than one water source is utilised for fish production, fish representing all water sources must be included in the sample;
• (iv) the fish selected must include fish collected in such a way that all production units, such as net cages, tanks and ponds, as well as all year classes in the establishment are proportionally represented in the sample.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits must be carried out and fish must be sampled in accordance with Section 1 and Table 2.

• 2.Samples which are collected in accordance with Section 1 and Table 2 must be tested using the diagnostic methods set out in point 2 of Section 5 of Chapter 2 of Part II and produce negative results for HPR-deleted ISAV.

Table 2

Surveillance programme for HPR-deleted ISAV

Risk level [^E0034]	Number of health visits per year to each establishment	Number of laboratory examinations per year	Number of fish in the sample
High	2	2 [^E0035]	30
Medium	1	1 [^E0036]	30
Low	1 every 2 years	1 every two years	30
Maximum number of fish per pool: 5	Maximum number of fish per pool: 5	Maximum number of fish per pool: 5	Maximum number of fish per pool: 5

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I

Samples must be collected during spring and autumn when two samples are required each year

Samples must be collected during spring or autumn when only one sample is required per year

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with HPR-deleted ISAV may restart a surveillance programme for that diseases provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using fish that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from infection with HPR-deleted ISAV;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for infection with HPR-deleted ISAV; or
• (iii) implementing a surveillance programme for infection with HPR-deleted ISAV.

CHAPTER 3

Requirements for establishments to demonstrate the implementation of a surveillance programme for infection with Marteilia refringens and requirements to re-start that programme following a disease outbreak

Section 1

General requirements for health visits and sampling for infection with Marteilia refringens

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) health visits and sampling for laboratory examination must be carried out in the period of the year when prevalence of the parasite in the Member State, zone or compartment is known to be maximal. When such data is not available, sampling shall be carried out just after the water temperature has exceeded 17 °C;

• (b) when molluscs are to be sampled in accordance with the requirements set out in Table 3, the following criteria must apply:
• (i) Ostrea spp. must be sampled. If Ostrea spp. are not present, the sample must be representative of all other listed species present;
• (ii) if weak, gaping or freshly dead but not decomposed molluscs are present in the production units, such molluscs must primarily be selected. If such molluscs are not present, the molluscs selected must include the oldest healthy molluscs;
• (iii) when sampling in mollusc establishments which utilise more than one water source for mollusc production, molluscs representing all water sources must be included for sampling in such a way that all parts of the establishment are proportionally represented in the sample;
• (iv) when sampling in mollusc establishments or groups of establishments, molluscs from a sufficient number of sampling points must be included in the sample in such a way that all parts of the establishment or group of establishments are proportionally represented in the sample. The main factors to be considered for the selection of those sampling points are stocking density, water flows, the presence of susceptible species, the presence of vector species, bathymetry and management practices. Natural beds within or adjacent to the establishment or group of establishments must be included in the sampling.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits must be carried out and molluscs must be sampled in accordance with Section 1 and Table 3.

• 2.Samples which are collected in accordance with Section 1 and Table 3 must be tested using the diagnostic methods set out in point 2 of Section 5 of Chapter 3 of Part II and produce negative results for Marteilia refringens.

Table 3

Surveillance programme for Marteilia refringens

Risk level [^E0037]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of molluscs in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 2 years	1 every 4 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with Marteilia refringens may re-start a surveillance programme for that disease provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using molluscs that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from infection with Marteilia refringens;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for infection with Marteilia refringens; or
• (iii) implementing a surveillance programme for infection with Marteilia refringens.

CHAPTER 4

Requirements for establishments to demonstrate the implementation of a surveillance programme for infection with Bonamia exitiosa and to re-start that programme following a disease outbreak

Section 1

General requirements for health visits and sampling for infection with Bonamia exitiosa

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) health visits and sampling of production units must be carried out in the period of the year when prevalence of Bonamia exitiosa in the Member State, zone or compartment is known to be maximal. When such data is not available, sampling shall be carried out twice a year, in spring and autumn;

• (b) when molluscs are sampled in accordance with the requirements set out in Table 4, the following criteria must apply:
• (i) if Ostrea spp. are present, only oysters of that species must be selected for sampling. If Ostrea spp. are not present, the sample must be representative of all other susceptible species present;
• (ii) if weak, gaping or freshly dead but not decomposed molluscs are present, such molluscs must primarily be selected. If such molluscs are not present, the molluscs selected must include the oldest healthy molluscs;
• (iii) when sampling in establishments which utilise more than one water source for mollusc production, molluscs representing all water sources must be included for sampling in such a way that all parts of the establishment are proportionally represented in the sample;
• (iv) when sampling in establishments or groups of establishments, molluscs from a sufficient number of sampling points must be included in the sample in such a way that all parts of the establishment or group of establishments are proportionally represented in the sample. The main factors to be considered for the selection of those sampling points are stocking density, water flows, the presence of susceptible species, the presence of vector species (e.g.Crassostrea gigas), bathymetry and management practices. Natural beds within or adjacent to the establishment or group of establishments must be included in the sampling.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits must be carried out and molluscs must be sampled in accordance with Section 1 and Table 4.

• 2.Samples which are collected in accordance with Section 1 and Table 4 must be tested using the diagnostic methods referred to in point 2 of Section 5 of Chapter 4 of Part II and produce negative results for Bonamia exitiosa.

Table 4

Surveillance programme for infection with Bonamia exitiosa

Risk level [^E0038]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of molluscs in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 2 years	1 every 4 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I.

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with Bonamia exitiosa may re-start a surveillance programme provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using molluscs that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from infection with Bonamia exitiosa;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for infection with Bonamia exitiosa; or
• (iii) implementing a surveillance programme for infection with Bonamia exitiosa.

CHAPTER 5

Requirements for establishments to demonstrate the implementation of a surveillance programme for infection with Bonamia ostreae and to re-start that programme following a disease outbreak

Section 1

General requirements for health visits and sampling for infection with Bonamia ostreae

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) health visits and sampling of production units shall be carried out in the period of the year when prevalence of Bonamia ostreae in the Member State, zone or compartment is known to be maximal. When such data is not available, sampling shall be carried out in winter or at the beginning of spring;

• (b) when molluscs are to be sampled in accordance with the requirements set out in Table 5, the following criteria must apply:
• (i) if Ostrea edulis are present, only oysters of that species must be selected for sampling. If Ostrea edulis are not present, the sample must be representative of all other susceptible species present;
• (ii) if weak, gaping or freshly dead but not decomposed molluscs are present, such molluscs must primarily be selected. If such molluscs are not present, the molluscs selected must include the oldest healthy molluscs;
• (iii) when sampling in establishments which utilise more than one water source for mollusc production, molluscs representing all water sources must be included for sampling in such a way that all parts of the establishment are proportionally represented in the sample;
• (iv) when sampling in mollusc establishments or groups of establishments, molluscs from a sufficient number of sampling points must be included in the sample. The main factors to be considered for the selection of those sampling points are stocking density, water flows, the presence of susceptible species, the presence of vector species, bathymetry and management practices. Natural beds within or adjacent to the establishment or group of establishments must be included in the sampling.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits must be carried out and molluscs must be sampled in accordance with Section 1 and Table 5.

• 2.Samples which are collected in accordance with Section 1 and Table 5 must be tested using the diagnostic methods referred to in point 2 of Section 5 of Chapter 5 of Part II and produce negative results for Bonamia ostreae.

Table 5

Surveillance programme for infection with Bonamia ostreae

Risk level [^E0039]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of molluscs in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 2 years	1 every 4 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with Bonamia ostreae may re-start the surveillance programme for that disease provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using molluscs that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from infection with Bonamia ostreae;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for infection with Bonamia ostreae; or
• (iii) implementing a surveillance programme for infection with Bonamia ostreae.

CHAPTER 6

Requirements for establishments to demonstrate the implementation of a surveillance programme for infection with WSSV and to re-start that programme following a disease outbreak

Section 1

General requirements for health visits and sampling for infection with infection with WSSV

The health visits and sampling referred to in point (b)(iv) of Article 3(2) must comply with the following requirements:

• (a) the sampling of crustaceans for laboratory examination must be carried out whenever the water temperature is likely to reach its highest annual point. That requirement concerning water temperature must also apply to health visits where these are feasible and appropriate;

• (b) when farmed crustaceans are to be sampled in accordance with the requirements set out in Table 6, the following criteria must apply:
• (i) if weak or moribund crustaceans are present in the production units, such crustaceans must primarily be selected. If such crustaceans are not present, those selected must include crustaceans of different size cohorts namely juveniles and adults, of the selected susceptible species, proportionally represented in the sample;
• (ii) if more than one water source is utilised for crustacean production, susceptible crustaceans representing all water sources must be included for sampling.

Section 2

Specific requirements to demonstrate the implementation of a surveillance programme

• 1.Health visits shall be carried out and crustaceans shall be sampled in accordance with Section 1 and Table 6.

• 2.Samples which are collected in accordance with Section 1 and Table 6 must be tested using the diagnostic methods referred to in point 2 of Section 5 of Chapter 6 of Part II and produce negative results for infection with WSSV.

Table 6

Surveillance programme for infection with WSSV

Risk level [^E0040]	Number of health visits to each establishment/group of establishments	Number of laboratory examinations	Number of crustaceans in the sample
High	1 every year	1 every 2 years	150
Medium	1 every 2 years	1 every 2 years	150
Low	1 every 2 years	1 every 4 years	150

Risk level assigned to the establishment by the competent authority as set out in paragraph 1 of Chapter 2 of Part I

Section 3

Requirements to re-start a surveillance programme after a disease outbreak

An establishment which has been infected with WSSV may re-start a surveillance programme for that disease provided that:

• (a) it has been emptied in accordance with Article 62, cleaned and disinfected in accordance with Article 63, and fallowed in accordance with Article 64; and

• (b) repopulation occurs using crustaceans that originate from establishments which are:
• (i) in a Member State, a zone or a compartment free from infection with WSSV;
• (ii) in a Member State, a zone or a compartment covered by an eradication programme for infection with WSSV; or
• (iii) implementing a surveillance programme for infection with WSSV.

[^E0003]: Directive 2003/99/EC of the European Parliament and of the Council of 17 November 2003 on the monitoring of zoonoses and zoonotic agents, amending Council Decision 90/424/EEC and repealing Council Directive 92/117/EEC (OJ L 325, 12.12.2003, p. 31).

[^E0004]: Council Directive 92/65/EEC of 13 July 1992 laying down animal health requirements governing trade in and imports into the Community of animals, semen, ova and embryos not subject to animal health requirements laid down in specific Community rules referred to in Annex A (I) to Directive 90/425/EEC (OJ L 268, 14.9.1992, p. 54).

[^E0005]: 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 (OJ L 328, 24.11.2006, p. 14).

[^E0006]: Regulation (EU) No 576/2013 of the European Parliament and of the Council of 12 June 2013 on the non-commercial movement of pet animals and repealing Regulation (EC) N0 998/2003 (OJ L 178, 28.6.2013, p. 1, ELI: http://data.europa.eu/eli/reg/2013/576/oj).

[^E0007]: Commission Regulation (EC) No 616/2009 of 13 July 2009 implementing Council Directive 2005/94/EC as regards the approval of poultry compartments and other captive birds compartments with respect to avian influenza and additional preventive biosecurity measures in such compartments (OJ L 181, 14.7.2009, p. 16).

[^E0014]: Regulation (EU) No 576/2013 of the European Parliament and of the Council of 12 June 2013 on the non-commercial movement of pet animals and repealing Regulation (EC) N0 998/2003 (OJ L 178, 28.6.2013, p. 1).

[^E0015]: Commission Delegated Regulation (EU) 2020/686 of 17 December 2019, supplementing Regulation (EU) 2016/429 of the European Parliament and of the Council as regards the approval of germinal product establishments and the traceability and animal health requirements for movements within the Union of germinal products of certain kept terrestrial animals (see page 1 of this Official Journal).