Chapter 9.1.

crayfish plague
(Aphanomyces astaci)

Article 9.1.1.

For the purposes of the Aquatic Code, crayfish plague means infection with Aphanomyces astaci Schikora. This organism is a member of a group commonly known as the water moulds (the Oomycetida). Common synonyms are listed in the corresponding chapter of the Aquatic Manual.

Information on methods for diagnosis are provided in the Aquatic Manual.

Article 9.1.2.

The recommendations in this Chapter apply to all species of crayfish in all three crayfish families (Cambaridae, Astacidae, and Parastacidae). These recommendations also apply to any other susceptible species referred to in the Aquatic Manual when traded internationally.

Article 9.1.3.

1. When authorising the importation or transit of the following commodities, the Competent Authorities should not require any crayfish plague related conditions, regardless of the crayfish plague status of the exporting country, zone or compartment.

   1. For the species referred to in Article 9.1.2. intended for any purpose:

      1. commodities treated in a manner that inactivates the disease agent e.g. boiled, canned or pasteurised products and some ready-to-eat meals; and crayfish oil and crayfish meal intended for use in feed;

      2. chemically extracted chitin;

      3. crayfish products made non-infectious through processing as dry feed (e.g. pelleted or extruded feed);

      4. biological samples preserved for diagnostic applications in such a manner as to inactivate the disease agent;

      5. frozen crayfish products that have been subjected to -20°C or lower temperatures for at least 72 hours.

   2. [The following products destined for human consumption from species referred to in Article 9.1.2. which have been prepared and packaged for direct retail trade:

   For the commodities listed in point 1b), OIE Members may wish to consider introducing internal measures to address the risks associated with the commodity being used for any purpose other than for human consumption. (under study)]

2. When authorising the importation or transit of the commodities of a species referred to in Article 9.1.2., other than those listed in point 1 of Article 9.1.3., the Competent Authorities should require the conditions prescribed in Articles 9.1.7. to 9.1.11. relevant to the crayfish plague status of the exporting country, zone or compartment.

3. When considering the importation/transit from an exporting country, zone or compartment not declared free of crayfish plague of a commodity of a species not covered in Article 9.1.2. but which could reasonably be expected to be a potential mechanical vector for A. astaci, the Competent Authorities should conduct a risk analysis in accordance with the recommendations in the Aquatic Code. The exporting country should be informed of the outcome of this assessment.

Article 9.1.4.

A country may make a self-declaration of freedom from crayfish plague if it meets the conditions in points 1, 2, 3 or 4 below.

If a country shares a zone with one or more other countries, it can only make a self-declaration of freedom from crayfish plague if all the areas covered by the shared water are declared crayfish plague free countries or zones (see Article 9.1.5.).

1. A country where none of the susceptible species referred to in Article 9.1.2. is present may make a self-declaration of freedom from crayfish plague when basic biosecurity conditions have been continuously met in the country for at least the past 2 years.

OR

2. A country where the susceptible species referred to in Article 9.1.2. are present but there has been no observed occurrence of the disease for at least the past 25 years despite conditions that are conducive to its clinical expression, as described in the corresponding chapter of the Aquatic Manual, may make a self-declaration of freedom from crayfish plague when basic biosecurity conditions have been continuously met in the country for at least the past 10 years.

OR

3. A country where the last observed occurrence of the disease was within the past 25 years or where the infection status prior to targeted surveillance was unknown (e.g. because of the absence of conditions conducive to its clinical expression as described in the corresponding chapter of the Aquatic Manual) may make a self-declaration of freedom from crayfish plague when:

   1. basic biosecurity conditions have been continuously met for at least the past 5 years; and

   2. targeted surveillance, as described in Chapter 1.4. of the Aquatic Code, has been in place for at least the last 5 years without detection of A. astaci.

OR

4. A country that has previously made a self-declaration of freedom from crayfish plague but in which the disease is subsequently detected may make a self-declaration of freedom from crayfish plague again when the following conditions have been met:

   1. on detection of the disease, the affected area was declared an infected zone and a buffer zone was established; and

   2. infected populations have been destroyed or removed from the infected zone by means that minimise the risk of further spread of the disease, and the appropriate disinfection procedures (see Aquatic Manual) have been completed; and

   3. targeted surveillance, as described in Chapter 1.4. of the Aquatic Code, has been in place for at least the past 5 years without detection of A. astaci; and

   4. previously existing basic biosecurity conditions have been reviewed and modified as necessary and have continuously been in place for at least the past 5 years.

   In the meantime, part of the non-affected area may be declared a free zone provided that such part meets the conditions in point 3 of Article 9.1.5.

Article 9.1.5.

A zone or compartment within the territory of one or more countries not declared free from crayfish plague may be declared free by the Competent Authority(ies) of the country(ies) concerned if the zone or compartment meets the conditions referred to in points 1, 2, 3 or 4 below.

If a zone or compartment extends over more than one country, it can only be declared a crayfish plague free zone or compartment if all the relevant Competent Authorities confirm that the conditions have been met.

1. A zone or compartment where none of the susceptible species referred to in Article 9.1.2. is present may be declared free from crayfish plague when basic biosecurity conditions have been continuously met in the zone or compartment for at least the past 2 years.

OR

2. A zone or compartment where the susceptible species referred to in Article 9.1.2. are present but in which there has not been any observed occurrence of the disease for at least the past 25 years despite conditions that are conducive to its clinical expression, as described in the corresponding chapter of the Aquatic Manual, may be declared free from crayfish plague when basic biosecurity conditions have been continuously met in the zone or compartment for at least the past 10 years.

OR

3. A zone or compartment where the last observed occurrence of the disease was within the past 25 years or where the infection status prior to targeted surveillance was unknown (e.g. because of the absence of conditions conducive to its clinical expression as described in the corresponding chapter of the Aquatic Manual) may be declared free from crayfish plague when:

   1. basic biosecurity conditions have been continuously met for at least the past 5 years; and

   2. targeted surveillance, as described in Chapter 1.4. of the Aquatic Code, has been in place, through the zone or compartment, for at least the past 5 years without detection of A. astaci.

OR

4. A zone previously declared free from crayfish plague but in which the disease is subsequently detected may be declared free from crayfish plague again when the following conditions have been met:

   1. on detection of the disease, the affected area was declared an infected zone and a buffer zone was established; and

   2. infected populations have been destroyed or removed from the infected zone by means that minimise the risk of further spread of the disease, and the appropriate disinfection procedures (see Aquatic Manual) have been completed; and

   3. targeted surveillance, as described in Chapter 1.4. of the Aquatic Code, has been in place for at least the past 5 years without detection of A. astaci; and

   4. previously existing basic biosecurity conditions have been reviewed and modified as necessary and have continuously been in place for at least the past 5 years.

Article 9.1.6.

A country, zone or compartment that is declared free from crayfish plague following the provisions of points 1 or 2 of Articles 9.1.4. or 9.1.5. (as relevant) may maintain its status as crayfish plague free provided that basic biosecurity conditions are continuously maintained.

A country, zone or compartment that is declared free from crayfish plague following the provisions of point 3 of Articles 9.1.4. or 9.1.5. (as relevant) may discontinue targeted surveillance and maintain its status as crayfish plague free provided that conditions that are conducive to clinical expression of crayfish plague, as described in the corresponding chapter of the Aquatic Manual, exist, and basic biosecurity conditions are continuously maintained.

However, for declared free zones or compartments in infected countries and in all cases where conditions are not conducive to clinical expression of crayfish plague, targeted surveillance needs to be continued at a level determined by the Competent Authority on the basis of the likelihood of infection.

Article 9.1.7.

When importing live aquatic animals of species referred to in Article 9.1.2. from a country, zone or compartment declared free from crayfish plague, the Competent Authority of the importing country should require an international aquatic animal health certificate issued by the Competent Authority of the exporting country or a certifying official approved by the importing country attesting that, on the basis of the procedures described in Articles 9.1.4. or 9.1.5. (as applicable), the place of production of the aquatic animal is a country, zone or compartment declared free from crayfish plague.

The certificate should be in accordance with the Model Certificate in Chapter 5.10.

This Article does not apply to commodities listed in point 1 of Article 9.1.3.

Article 9.1.8.

1. When importing, for aquaculture, live aquatic animals of species referred to in Article 9.1.2. from a country, zone or compartment not declared free from crayfish plague, the Competent Authority of the importing country should assess the risk and, if justified, apply the following risk mitigation measures:

   1. the direct delivery to and lifelong holding of the consignment in biosecure facilities for continuous isolation from the local environment; and

   2. the treatment of all effluent and waste materials in a manner that ensures inactivation of A. astaci.

2. If the intention of the introduction is the establishment of a new stock, the Code of Practice on the Introductions and Transfers of Marine Organisms of the International Council for the Exploration of the Seas (ICES) should be followed.

3. For the purposes of the Aquatic Code, the ICES Code (full version see: http://www.ices.dk/indexfla.asp) may be summarised to the following main points:

   1. identify stock of interest (cultured or wild) in its current location;

   2. evaluate stock health/disease history;

   3. take and test samples for A. astaci, pests and general health/disease status;

   4. import and quarantine in a secure facility a founder (F-0) population;

   5. produce F-1 generation from the F-0 stock in quarantine;

   6. culture F-1 stock and at critical times in its development (life cycle) sample and test for A. astaci and perform general examinations for pests and general health/disease status;

   7. if A. astaci is not detected, pests are not present, and the general health/disease status of the stock is considered to meet the basic biosecurity conditions of the importing country, zone or compartment, the F-1 stock may be defined as crayfish plague free or specific pathogen free (SPF) for A. astaci;

   8. release SPF F-1 stock from quarantine for aquaculture or stocking purposes in the country, zone or compartment.

This Article does not apply to commodities listed in point 1 of Article  9.1.3.

Article 9.1.9.

When importing, for human consumption, live aquatic animals of species referred to in Article 9.1.2. from a country, zone or compartment not declared free from crayfish plague, the Competent Authority of the importing country should assess the risk and, if justified, require that:

1. the consignment be delivered directly to and held in isolation until processing and/or consumption; and

2. all effluent, dead aquatic animals and waste materials from the processing be treated in a manner that ensures inactivation of A. astaci.

OIE Members may wish to consider introducing internal measures to prevent such commodities being used for any purpose other than for human consumption.

This Article does not apply to commodities listed in point 1 of Article 9.1.3.

Article 9.1.10.

When importing aquatic animal products of species referred to in Article 9.1.2. from a country, zone or compartment declared free from crayfish plague, the Competent Authority of the importing country should require an international aquatic animal health certificate issued by the Competent Authority of the exporting country or a certifying official approved by the importing country attesting that, on the basis of the procedures described in Articles 9.1.4. or 9.1.5. (as applicable), the place of production of the consignment is a country, zone or compartment declared free from crayfish plague.

The certificate should be in accordance with the Model Certificate in Chapter 5.10.

This Article does not apply to commodities listed in point 1 of Article 9.1.3.

Article 9.1.11.

When importing aquatic animal products of species referred to in Article 9.1.2. from a country, zone or compartment not declared free from crayfish plague, the Competent Authority of the importing country should assess the risk and apply appropriate risk mitigation measures.

This Article does not apply to commodities listed in point 1 of Article 9.1.3.