Chapter 4.1.

Zoning and compartmentalisation

Article 4.1.1.

Given the difficulty of establishing and maintaining freedom from a particular disease for an entire country especially for diseases whose entry is difficult to control, there may be benefits to one or more Members in establishing and maintaining a subpopulation with a distinct aquatic animal health status. Subpopulations may be separated by natural or artificial geographical barriers or, in certain situations, by the application of appropriate management practices.

Zoning and compartmentalisation are procedures implemented by a country under the provisions of this chapter to define subpopulations of distinct aquatic animal health status for the purpose of disease control or international trade. Compartmentalisation applies to a subpopulation when management practices related to biosecurity are the defining factors, while zoning applies when a subpopulation is defined on a geographical basis. In practice, spatial considerations and good management play important roles in the application of both concepts.

This chapter is to assist OIE Members wishing to establish and maintain different subpopulations, using the principles of compartmentalisation and zoning. These principles should be applied in accordance with the measures recommended in the relevant disease chapter(s). This chapter also outlines a process through which trading partners may recognise such subpopulations. This process is best implemented by trading partners through establishing parameters and gaining agreement on the necessary measures prior to outbreaks of disease.

Before trade in aquatic animals or aquatic animal products may occur, an importing country needs to be satisfied that its aquatic animal health status will be appropriately protected. In most cases, the import regulations developed will rely in part on judgements made about the effectiveness of sanitary procedures undertaken by the exporting country, both at its borders and within its territory.

In addition to contributing to the safety of international trade, zoning and compartmentalisation may assist disease control or eradication within Members. Zoning may encourage the more efficient use of resources, and compartmentalisation may allow the functional separation of a subpopulation from other domestic or wild aquatic animals through biosecurity measures, which a zone (through geographical separation) would not achieve. Following an outbreak of disease, compartmentalisation may allow a Member be able to take advantage of epidemiological links among subpopulations or common practices relating to biosecurity, despite diverse geographical locations, to facilitate disease control and/or the resumption of trade.

Zoning and compartmentalisation may not be applicable to all diseases, but separate requirements will be developed for each disease for which the application of zoning or compartmentalisation is considered appropriate.

To regain the status of a free zone or free compartment following an outbreak of disease, Members should follow the recommendations in the relevant disease chapter in the Aquatic Code.

Article 4.1.2.

The Competent Authority of an exporting country that is establishing a zone or compartment for international trade purposes should clearly define the subpopulation in accordance with the recommendations in the relevant chapters in the Aquatic Code, including those on surveillance, and the identification and traceability of aquatic animals. The Competent Authority of an exporting country should be able to explain to the Competent Authority of an importing country the basis for its claim of a distinct aquatic animal health status for the zone or compartment in such terms.

The procedures used to establish and maintain the distinct aquatic animal health status of a zone or compartment should be appropriate to the particular circumstances and will depend on the epidemiology of the disease, environmental factors, risk of introduction and establishment of disease, and applicable biosecurity measures. The exporting country should be able to demonstrate, through detailed documentation supplied to the importing country, published through official channels, that it has implemented the recommendations in the Aquatic Code for establishing and maintaining such a zone or compartment.

An importing country should recognise the existence of this zone or compartment when the appropriate measures recommended in the Aquatic Code are applied, and the Competent Authority of the exporting country certifies that this is the case. Note that an importing country may adopt a higher level of protection where it is scientifically justified and the obligations referred to in Article 2.1.2. are met. Article 4.1.4. is also relevant.

Where countries share a zone or compartment, the Competent Authority of each country should collaborate to define and fulfil their respective responsibilities.

The exporting country should conduct an assessment of the resources needed and available to establish and maintain a zone or compartment for international trade purposes. These include the human and financial resources and the technical capability of the Competent Authority (and of the relevant industry, in the case of a compartment) including on disease surveillance and diagnosis.

Article 4.1.3.

In conjunction with the above considerations and the definitions of zone and compartment, the following principles should apply when Members define a zone or compartment:

1. The extent of a zone should be established by the Competent Authority on the basis of the definition of zone and made public through official channels.

2. The factors defining a compartment should be established by the Competent Authority on the basis of relevant criteria such as management and husbandry practices related to biosecurity, and made public through official channels.

3. Aquatic animals belonging to such subpopulations need to be recognizable as such through a clear epidemiological separation from other aquatic animals and all things presenting a disease risk.

4. For a zone or compartment, the Competent Authority should document in detail the measures taken to ensure the identification of the subpopulation, for example by means of registration of all the aquaculture establishments located in such a zone or compartment and the establishment and maintenance of its aquatic animal health status through a biosecurity plan. The measures used to establish and maintain the distinct aquatic animal health status of a zone or compartment should be appropriate to the particular circumstances and will depend on the epidemiology of the disease, environmental factors, the aquatic animal health status in adjacent areas, applicable biosecurity measures (including movement controls, use of natural and artificial boundaries, the spatial separation of aquatic animals, and commercial management and husbandry practices), and surveillance.

5. For a compartment, the biosecurity plan should describe the partnership between the relevant enterprise/industry and the Competent Authority, and their respective responsibilities, including the procedures for oversight of the operation of the compartment by the Competent Authority.

6. For a compartment, the biosecurity plan should also describe the routine operating procedures to provide clear evidence that the surveillance conducted and the management practices are adequate to meet the definition of the compartment. In addition to information on aquatic animal movements, the biosecurity plan should include production and stock records, feed sources, traceability, surveillance results, visitor logbook, morbidity and mortality history, medications, vaccinations, documentation of training and any other criteria necessary for evaluation of risk mitigation. The information required may vary according to the aquatic animal species and disease(s) under consideration. The biosecurity plan should also describe how the measures will be audited to ensure that the risks are regularly re-assessed and the measures adjusted accordingly.

7. Thus defined, the zones and compartments constitute the relevant subpopulations for the application of the recommendations in Section 8. to Section 11. of of the Aquatic Code.

Article 4.1.4.

There is no single sequence of steps which should be followed in establishing a zone or a compartment. The steps that the Competent Authority of the importing country and the exporting country choose and implement will generally depend on the circumstances existing within the countries and at their borders, and their trading history. The recommended steps are:

1. For zoning

   1. The exporting country identifies a geographical area, which it considers to contain an aquatic animal subpopulation with a distinct aquatic animal health status with respect to a specific disease/specific diseases, based on surveillance.

   2. The exporting country describes in the biosecurity plan for the zone the measures which are being, or will be, applied to distinguish such an area epidemiologically from other parts of its territory, in accordance with the recommendations in the Aquatic Code.

   3. The exporting country provides the above information to the importing country, with an explanation of why the area can be treated as an epidemiologically separated zone for international trade purposes.

   4. The importing country determines whether it accepts such an area as a zone for the importation of aquatic animals and aquatic animal products, taking into account:

      1. an evaluation of the exporting country's Competent Authority;

      2. the result of a risk assessment based on the information provided by the exporting country and its own research;

      3. its own aquatic animal health situation with respect to the disease(s) concerned; and

      4. other relevant OIE standards.

   5. The importing country notifies the exporting country of the result of its determination and the underlying reasons, within a reasonable period of time, being either:

      1. recognition of the zone;

      2. request for further information; or

      3. rejection of the area as a zone for international trade purposes.

   6. An attempt should be made to resolve any differences over the recognition of the zone, either in the interim or finally, by using an agreed mechanism to reach consensus (such as the OIE dispute settlement mechanism).

   7. The importing country and the exporting country should enter into a formal agreement recognising the zone.

2. For compartmentalisation

   1. Based on discussions with the relevant enterprise/industry, the exporting country identifies a compartment of one or more aquaculture establishments or other premises that operate under common management practices related to biosecurity, and which contains an identifiable aquatic animal subpopulation with a distinct aquatic animal health status with respect to a specific disease/specific diseases; the exporting country describes how this status is maintained through a partnership between the relevant enterprise/industry and the Competent Authority of the exporting country.

   2. The exporting country examines the compartment’s biosecurity plan and confirms through an audit that:

      1. the compartment is epidemiologically closed throughout its routine operating procedures as a result of effective implementation of its biosecurity plan; and

      2. the surveillance programme in place is appropriate to verify the status of such aquaculture establishment(s) with respect to such disease(s).

   3. The exporting country describes the compartment, in accordance with the recommendations in the Aquatic Code.

   4. The exporting country provides the above information to the importing country, with an explanation of why such an enterprise can be treated as an epidemiologically separated compartment for international trade purposes.

   5. The importing country determines whether it accepts such an enterprise as a compartment for the importation of aquatic animals and aquatic animal products, taking into account:

      1. an evaluation of the exporting country's Competent Authority;

      2. the result of a risk assessment based on the information provided by the exporting country and its own research;

      3. its own aquatic animal health situation with respect to the disease(s) concerned; and

      4. other relevant OIE standards.

   6. The importing country notifies the exporting country of the result of its examination and the underlying reasons, within a reasonable period of time, being either:

      1. recognition of the compartment;

      2. request for further information; or

      3. rejection of such an enterprise as a compartment for international trade purposes.

   7. An attempt should be made to resolve any differences over the recognition of the compartment, either in the interim or finally, by using an agreed mechanism to reach consensus (such as the OIE dispute settlement mechanism).

   8. The importing country and the exporting country should enter into a formal agreement recognising the compartment.