Chapter 8.2.

Aujeszky's disease

Article 8.2.1.

The Aujeszky's disease (AD) free or provisionally free status of a country or zone can only be determined if the following conditions are fulfilled:

1. a risk assessment has been conducted identifying all potential factors for AD occurrence and their historic perspective;

2. AD is notifiable in the whole country, and all clinical cases suggestive of AD are subjected to field and laboratory investigations;

3. an on-going awareness programme is in place to encourage reporting of all cases suggestive of AD in susceptible species;

4. the Veterinary Authority has current knowledge of, and authority over, all establishments containing pigs in the whole country;

5. domestic pigs are properly identified when leaving their establishment of origin with an indelible mark giving the identification number of their herd of origin; a reliable tracing back procedure is in place for all pigs leaving their establishment of origin.

An AD infected establishment means an establishment in which the virus has been isolated or identified, or a positive serological result (total or gE antibodies) has been confirmed in a laboratory.

Standards for diagnostic tests and vaccines are described in the Terrestrial Manual.

Article 8.2.2.

1. Qualification

   A country or zone may be considered free from the disease without formally applying a specific surveillance programme (historical freedom) if the disease has not been reported for at least 25 years, and if for at least the past 10 years:

   1. it has been a notifiable disease;

   2. an early detection system has been in place;

   3. measures to prevent the introduction of the AD virus into the country or zone have been in place;

   4. no vaccination against the disease has been carried out;

   5. infection is not known to be established in wild swine, or measures have been implemented to prevent any transmission of the AD virus from wild swine to domestic pigs.

   A country or zone which does not meet the conditions of the above paragraph may be considered free from AD when:

   6. animal health regulations to control the movement of commodities listed in Article 8.2.6. in order to prevent the introduction of infection into the establishments of the country or zone have been in place for at least 2 years;

   7. vaccination against AD has been banned for all domestic pigs in the country or zone for at least 2 years;

   8. if AD has never been reported in the country or zone, serological surveys, with negative results, have been conducted on a representative sample of all pig establishments in conformity with the recommendations in Chapter X.X. (under study) no more than 3 years prior to qualification; the serological surveys should be directed at the detection of antibodies to the whole virus, and based on the breeding pig population or, for establishments that contain no breeding pigs, on a comparable number of fattening pigs; or

   9. if AD has been reported in the country or zone, a surveillance and control programme has been in place to detect every infected establishment and eradicate AD from it; the surveillance programme should be carried out in conformity with the recommendations in Chapter X.X. (under study) and demonstrate that no establishments within the country or zone have had any clinical, virological or serological evidence of AD for at least 2 years.

   In order for a country to reach free status, all of its zones must have reached AD free status.

   In countries or zones with wild swine, measures should be implemented to prevent any transmission of the AD virus from wild swine to domestic pigs.

2. Maintenance of free status

   In order to maintain its free status, a country or zone should comply with the following requirements:

   1. periodic serological surveys directed at the detection of antibodies to the whole AD virus should be carried out on a statistically significant number of breeding pigs, in conformity with the recommendations in Chapter X.X. (under study);

   2. the importation of the commodities listed in Article 8.2.6. into the country or zone is carried out in conformity with the import conditions contained in the relevant Articles of the present Chapter;

   3. the ban on AD vaccination remains in force;

   4. measures aimed at preventing the transmission of the AD virus from wild swine to domestic pigs remain in force.

3. Recovery of free status

   Should an AD outbreak occur in an establishment of a free country or zone, the status of the country or zone may be restored if either:

   1. all the pigs in the outbreak have been slaughtered; and, during and after the application of this measure, an epidemiological investigation including clinical examination, and serological and/or virological testing has been carried out in all pig establishments which have been directly or indirectly in contact with the infected establishment and in all pig establishments located within a 5-kilometre radius of the outbreak, demonstrating that these establishments are not infected; or

   2. vaccination with gE- deleted vaccines has been applied and:

      1. a serological testing procedure (differential ELISA) has been implemented in the establishments where vaccination has been applied to demonstrate the absence of infection;

      2. the movement of pigs from these establishments has been banned, except for immediate slaughter, until the above procedure has demonstrated the absence of infection;

      3. all vaccinated animals have been slaughtered;

      4. during and after the application of the measures described in points i) to iii) above, a thorough epidemiological investigation including clinical examination and serological and/or virological testing has been carried out in all pig establishments which have been directly or indirectly in contact with the infected establishment and in all pig establishments located within a 5-kilometre radius of the outbreak, demonstrating that these establishments are not infected.

Article 8.2.3.

1. Qualification

   A country or zone may be considered as provisionally free from AD if the following conditions are complied with:

   1. animal health regulations to control the movement of commodities listed in Article 8.2.6. in order to prevent the introduction of infection into the establishments of the country or zone have been in place for at least 2 years;

   2. if AD has never been reported in the country or zone, a serological survey, with negative results, has been conducted on a representative sample of all pig establishments in conformity with the recommendations in Chapter X.X. (under study) (at a level of confidence not sufficient to meet requirements for freedom); the serological survey should be directed at the detection of antibodies to the whole virus, and based on the breeding pig population or, for establishments that contain no breeding pigs, on a comparable number of fattening pigs; or

   3. if AD has been reported in the country or zone, a surveillance and control programme has been in place to detect infected establishments and eradicate AD from these establishments, the herd prevalence rate in the country or zone has not exceeded 1% for at least 3 years (the sampling procedure described in point 1e) of the definition of ‘AD free establishment’ should be applied within the establishments of the country or zone), and at least 90% of the establishments in the country or zone are qualified free;

   4. in countries or zones with wild swine, measures should be taken to prevent any transmission of the AD virus between wild swine and domestic pigs.

2. Maintenance of provisionally free status

   In order to maintain its provisionally free status, a country or zone should comply with the following requirements:

   1. the measures described in points 1b) and 1d) above should be continued;

   2. the percentage of infected establishments remains <1%;

   3. the importation of the commodities listed in Article 8.2.6. into the country or zone is carried out in conformity with the import conditions contained in the relevant Articles of the present Chapter.

3. Recovery of provisionally free status

   Should the percentage of infected establishments exceed 1% in a provisionally free country or zone, the status of the country or zone is cancelled and may be restored only once the percentage of infected establishments has remained <1% for at least 6 months, and this result is confirmed by a serological survey conducted in conformity with point 1c) above.

Article 8.2.4.

Countries and zones which do not fulfil the conditions to be considered free or provisionally free of AD should be considered as infected.

Article 8.2.5.

1. Qualification

   To qualify as free from AD, an establishment should satisfy the following conditions:

   1. it is under the control of the Veterinary Authority;

   2. no clinical, virological or serological evidence of AD has been found for at least one year;

   3. the introduction of pigs, semen and embryos/ova into the establishment is carried out in conformity with the import conditions for these commodities contained in the relevant Articles of the present Chapter;

   4. vaccination against AD has not been carried out in the establishment for at least 12 months, and any previously vaccinated pigs are free from gE antibodies;

   5. a number of breeding pigs from the establishment has been subjected, with negative results, to serological tests to the whole AD virus, applying a sampling procedure set out in conformity with the recommendations in Chapter X.X. (under study); these tests must have been carried out on two occasions, at an interval of 2 months; for establishments that contain no breeding pigs, the tests should be carried out only once on a comparable number of fattening or weaning pigs;

   6. a surveillance and control programme has been in place to detect infected establishments located within a 5-kilometre radius of the establishment and no establishment is known to be infected within this zone.

2. Maintenance of free status

   For establishments located in an infected country or infected zone, the testing procedure described in point 1e) above should be carried out every 4 months.

   For establishments located in a provisionally free country or zone, the testing procedure described in point 1e) above should be carried out every year.

3. Recovery of free status

   Should a free establishment become infected, or should an outbreak occur within a 5-kilometre radius of a free establishment, the free status of the establishment should be suspended until the following conditions are met:

   1. in the infected establishment:

      1. all the pigs in the establishment have been slaughtered, or

      2. at least 30 days after removal of all infected animals, all breeding animals have been subjected to a serological test to the whole AD virus, with negative results, on two occasions, at an interval of 2 months;

   2. in other establishments located in the 5-kilometre radius zone: a number of breeding pigs from each establishment has been subjected, with negative results, to serological tests to the whole AD virus (non vaccinated establishments) or to gE antibodies (vaccinated establishments), applying the sampling procedure described in point 1e above.

Article 8.2.6.

Commodities other than those listed below are not considered to have the potential to spread AD when they are the subject of international trade.

Veterinary Authorities of countries shall consider whether there is a risk with regard to AD in accepting importation or transit through their territory, from other countries, of the following commodities:

1. domestic and wild swine;

2. semen of domestic and wild swine;

3. embryos/ova of domestic and wild swine;

4. offal (head, and thoracic and abdominal viscera) of swine and products containing swine offal;

5. pathological material and biological products (see Chapter 5.8.).

Article 8.2.7.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the animals:

1. showed no clinical sign of AD on the day of shipment;

2. come from an establishment located in an AD free country or zone;

3. have not been vaccinated against AD.

Article 8.2.8.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the animals:

1. showed no clinical sign of AD on the day of shipment;

2. have been kept exclusively in AD free establishments since birth;

3. have not been vaccinated against AD;

4. were subjected to a serological test to the whole AD virus, with negative results, within 15 days prior to shipment.

Article 8.2.9.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the animals:

1. showed no clinical sign of AD on the day of shipment;

2. were kept exclusively in AD free establishments since birth;

3. have not been vaccinated against AD;

4. were isolated in the establishment of origin or a quarantine station, and were subjected to a serological test to the whole AD virus, with negative results, on two occasions, at an interval of not less than 30 days between each test, the second test being performed during the 15 days prior to shipment.

Article 8.2.10.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. a surveillance and control programme is in place in the country or zone to detect infected establishments and eradicate AD;

2. the animals:

   1. are not being eliminated as part of an eradication programme;

   2. showed no clinical sign of AD on the day of shipment;

   3. have been kept exclusively in AD free establishments since birth; or

   4. have been vaccinated against AD at least 15 days prior to shipment.

[Note: Appropriate precautions should be taken both by the exporting country and the importing country to ensure that the pigs are transported directly from the place of shipment to the abattoir for immediate slaughter.]

Article 8.2.11.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the animals:

1. showed no clinical sign of AD on the day of shipment;

2. were captured in an AD free country or zone;

3. have not been vaccinated against the disease;

4. were isolated in a quarantine station, and were subjected to a serological test to the whole AD virus, with negative results, on two occasions, at an interval of not less than 30 days between each test, the second test being performed during the 15 days prior to shipment.

Article 8.2.12.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor animals:

   1. showed no clinical sign of AD on the day of collection of the semen;

   2. were kept in an establishment or artificial insemination centre located in an AD free country or zone at the time of semen collection;

2. the semen was collected, processed and stored in conformity with the provisions of Chapter 4.6.

Article 8.2.13.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor animals:

   1. have been kept for at least 4 months prior to semen collection in an artificial insemination centre which has the status of AD free establishment, and where all boars are subjected to a serological test to the whole AD virus, with negative results, every 4 months;

   2. showed no clinical sign of AD on the day of collection;

2. the semen was collected, processed and stored in conformity with the provisions of Chapter 4.6.

Article 8.2.14.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor animals:

   1. were kept in an AD free establishment for at least 6 months prior to entering the artificial insemination centre;

   2. have been kept for at least 4 months prior to semen collection in the artificial insemination centre which has the status of AD free establishment, and where all boars are subjected to a serological test to the whole AD virus, with negative results, every 4 months;

   3. were subjected to a serological test to the whole AD virus, with negative results, within 10 days prior to or 21 days after semen collection;

   4. showed no clinical sign of AD on the day of collection;

2. the semen was collected, processed and stored in conformity with the provisions of Chapter 4.6.

Article 8.2.15.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor females:

   1. showed no clinical sign of AD on the day of collection of the embryos;

   2. were kept in an establishment located in an AD free country or zone prior to collection;

2. the embryos were collected, processed and stored in conformity with the provisions of Chapter 4.7.

Article 8.2.16.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor females:

   1. showed no clinical sign of AD on the day of collection of the embryos;

   2. were kept in an AD free establishment for at least 3 months prior to collection;

2. the embryos were collected, processed and stored in conformity with the provisions of Chapter 4.7.

Article 8.2.17.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. the donor females:

   1. showed no clinical sign of AD on the day of collection of the embryos;

   2. were kept in an AD free establishment for at least 3 months prior to collection;

   3. were subjected to a serological test to the whole AD virus, with negative results, within 10 days prior to collection;

2. the embryos were collected, processed and stored in conformity with the provisions of Chapter 4.7.

Article 8.2.18.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the entire consignment of offal or products containing pig offal comes from animals which come from establishments located in an AD free country or zone.

Article 8.2.19.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that the entire consignment of offal comes from animals:

1. which have been kept in an AD free establishment since birth;

2. which have not been in contact with animals from establishments not considered free from AD during their transport to the approved abattoir and therein.

Article 8.2.20.

Veterinary Authorities should require the presentation of an international veterinary certificate attesting that:

1. either the entire consignment of offal used to prepare the products complied with the conditions referred to in Article 8.2.19.; or

2. the products have been processed to ensure the destruction of the AD virus; and

3. the necessary precautions were taken after processing to avoid contact of the products with any source of AD virus.