Zoning and compartmentalisation

Article 4.3.1.

Introduction

For the purposes of the Terrestrial Code, ‘zoning’ and ‘regionalisation’ have the same meaning.

Establishing and maintaining a disease free status throughout the country should be the final goal for Member Countries. However, given the difficulty of establishing and maintaining a disease free status for an entire territory, especially for diseases the entry of which is difficult to control through measures at national boundaries, there may be benefits to a Member Country in establishing and maintaining a subpopulation with a distinct health status within its territory. 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 Member Country under the provisions of this chapter with a view to defining subpopulations of distinct health status within its territory for the purpose of disease control and/or international trade. While zoning applies to an animal subpopulation defined primarily on a geographical basis (using natural, artificial or legal boundaries), compartmentalisation applies to an animal subpopulation defined primarily by management and husbandry practices related to biosecurity. In practice, spatial considerations and good management including biosecurity plans play important roles in the application of both concepts.

A particular application of the concept of zoning is the establishment of a containment zone. In the event of limited outbreaks of a specified disease within an otherwise free country or zone, a single containment zone, which includes all cases, can be established for the purpose of minimizing the impact on the entire country or zone.

This chapter is to assist Member Countries wishing to establish and maintain different subpopulations within their territory 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 animals or their products may occur, an importing country needs to be satisfied that its 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.

As well as contributing to the safety of international trade, zoning and compartmentalisation may assist disease control or eradication within a Member Country's territory. Zoning may encourage the more efficient use of resources within certain parts of a country and compartmentalisation may allow the functional separation of a subpopulation from other domestic animals or wild animals through biosecurity measures, which a zone (through geographical separation) would not achieve. Following a diseaseoutbreak, the use of compartmentalisation may allow a Member Country 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 continuation of trade.

Zoning and compartmentalisation cannot be applied 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 free status following a disease outbreak in a zone or compartment, Member Countries should follow the recommendations in the relevant disease chapter in the Terrestrial Code.

Article 4.3.2.

General considerations

The Veterinary Services of an exporting country which is establishing a zone or compartment within its territory for international trade purposes should clearly define the subpopulation in accordance with the recommendations in the relevant chapters in the Terrestrial Code, including those on surveillance, and the identification and traceability of live animals. The Veterinary Services of an exporting country should be able to explain to the Veterinary Services of an importing country the basis for claiming a distinct animal health status for the given zone or compartment under consideration.

The procedures used to establish and maintain the distinct animal health status of a zone or compartment will depend on the epidemiology of the disease, in particular the presence and role of susceptible wildlife species, and environmental factors, as well as on the application of biosecurity measures.

The authority, organisation and infrastructure of the Veterinary Services, including laboratories, should be clearly documented in accordance with the chapter on the evaluation of Veterinary Services of the Terrestrial Code, to provide confidence in the integrity of the zone or compartment. The final authority of the zone or compartment, for the purposes of domestic and international trade, lies with the Veterinary Authority.

In the context of maintaining the health status of a population, references to ‘import’, ‘importation’ and ‘imported animals/products’ found in the Terrestrial Code apply both to importation into a country and to the movement of animals and their products into zones and compartments. Such movements should be the subject of appropriate measures to preserve the animal health status of the zone/compartment.

The exporting country should be able to demonstrate, through detailed documentation provided to the importing country, that it has implemented the recommendations in the Terrestrial 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 Terrestrial Code are applied and the Veterinary Authority of the exporting country certifies that this is the case.

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 Veterinary Services (and of the relevant industry and production system, in the case of a compartment) including diseasesurveillance and diagnosis.

Biosecurity and surveillance are essential components of zoning and compartmentalisation, and the arrangements should be developed through cooperation of industry and Veterinary Services.

Industry’s responsibilities include the application of biosecurity measures, documenting and recording movements of animals and personnel, quality assurance schemes, monitoring the efficacy of the measures, documenting corrective actions, conducting surveillance, rapid reporting and maintenance of records in a readily accessible form.

The Veterinary Services should provide movement certification, and carry out documented periodic inspections of facilities, biosecurity measures, records and surveillance procedures. Veterinary Services should conduct or audit surveillance, reporting and laboratory diagnostic examinations.

Article 4.3.3.

Principles for defining and establishing a zone or compartment, including protection and containment zones

In conjunction with the above considerations, the following principles should apply when Member Countries define a zone or a compartment.

1. The extent of a zone and its geographical limits should be established by the Veterinary Authority on the basis of natural, artificial and/or legal boundaries, and made public through official channels.

2. A protection zone may be established to preserve the health status of animals in a free country or zone, from adjacent countries or zones of different animal health status. Measures should be implemented based on the epidemiology of the disease under consideration to prevent introduction of the pathogenic agent and to ensure early detection.

   These measures should include intensified movement control and surveillance and may include:

   1. animal identification and animal traceability to ensure that animals in the protection zone are clearly distinguishable from other populations;

   2. vaccination of all or at risk susceptible animals;

   3. testing and/or vaccination of animals moved;

   4. specific procedures for sample handling, sending and testing;

   5. enhanced biosecurity including cleansing – disinfection procedures for transport means, and possible compulsory routes;
      

   6. specific surveillance of susceptible wildlife species and relevant vectors;
      

   7. awareness campaigns to the public or targeted at breeders, traders, hunters, veterinarians.

   The application of these measures can be in the entire free zone or in a defined area within and/or outside the free zone.
   

3. In the event of limited outbreaks in a country or zone previously free of a disease, a containment zone may be established for the purposes of trade. Establishment of a containment zone should be based on a rapid response including:
   

   1. appropriate standstill of movement of animals and other commodities upon notification of suspicion of the specified disease and the demonstration that the outbreaks are contained within this zone through epidemiological investigation (trace-back, trace-forward) after confirmation of infection. The primary outbreak has been identified and investigations on the likely source of the outbreak have been carried out and all cases shown to be epidemiologically linked.
      

   2. A stamping-out policy or another effective control strategy aimed at eradicating the disease should be applied and the susceptible animal population within the containment zones should be clearly identifiable as belonging to the containment zone. Increased passive and targeted surveillance in accordance with Chapter 1.4. in the rest of the country or zone should be carried out and has not detected any evidence of infection.
      

   3. Measures consistent with the disease-specific chapter should be in place to prevent spread of the infection from the containment zone to the rest of the country or zone, including ongoing surveillance in the containment zone.
      

   4. For the effective establishment of a containment zone, it is necessary to demonstrate that there have been no new cases in the containment zone within a minimum of two incubation periods from the last detected case.

   5. The free status of the areas outside the containment zone would be suspended pending the establishment of the containment zone. The free status of these areas could be reinstated, once the containment zone is clearly established, irrespective of the provisions of the disease-specific chapter.

   6. The containment zone should be managed in such a way that it can be demonstrated that commodities for international trade can be shown to have originated outside the containment zone.

   7. The recovery of the free status of the containment zone should follow the provisions of the disease-specific chapter.

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

5. Animals and herds belonging to such subpopulations need to be recognisable as such through a clear epidemiological separation from other animals and all things presenting a diseaserisk. For a zone or compartment, the Veterinary Authority should document in detail the measures taken to ensure the identification of the subpopulation and the establishment and maintenance of its health status through a biosecurity plan. The measures used to establish and maintain the distinct 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 health status of animals in adjacent areas, applicable biosecurity measures (including movement controls, use of natural and artificial boundaries, the spatial separation of animals, and commercial management and husbandry practices), and surveillance.

6. Relevant animals within the zone or compartment should be identified in such a way that their movements are traceable. Depending on the system of production, identification may be done at the herd, flock lot or individual animal level. Relevant animal movements into and out of the zone or compartment should be well documented and controlled. The existence of a valid animal identification system is a prerequisite to assess the integrity of the zone or compartment.

7. For a compartment, the biosecurity plan should describe the partnership between the relevant industry and the Veterinary Authority, and their respective responsibilities. It should also describe the routine operating procedures to provide clear evidence that the surveillance conducted, the live animal identification and traceability system, and the management practices are adequate to meet the definition of the compartment. In addition to information on animal movement controls, the plan should include herd or flock production records, feed sources, surveillance results, birth and death records, visitor logbook, morbidity and mortality history, medications, vaccinations, documentation of training of relevant personnel and any other criteria necessary for evaluation of risk mitigation. The information required may vary in accordance with the 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.