Division 5 Sampling of pigs

Particularly on farms that keep both pigs and poultry, either mixed or in separate houses, pigs are at risk of becoming infected with AI directly or indirectly via contact with poultry or poultry products. To exclude such infection, oropharyngeal or nasal swabs and blood samples must be collected according to the procedures described in point 8.21 of Chapter IV. Samples must be obtained from pigs that show clinical signs of the disease. However, when they do not show any clinical signs, samples may be collected at random over all sections of the house. If available in the laboratory, swabs must be tested in rapid molecular tests and/or virus isolation. The RT-PCR must have been appropriately validated and have a sensitivity at least equivalent to virus isolation in eggs for influenza A viruses.

Two to four weeks after culling of the AI infected poultry, at least 60 blood samples must be collected from pigs in such a way that at least some samples are obtained from groups of pigs that are in direct contact with each other. Samples must be tested in the HI test using virus derived from the poultry outbreak. Samples from both the acute and convalescent phases must be tested in the same test. Positive samples can be confirmed using virus neutralisation and/or Western blot analyses.

When any of those samples test positive, an epidemiological investigation on all pig farms located within the protection zone must be carried out, irrespective whether they are of mixed type or not.