Division II.3 Diagnostic criteria to confirm of the presence of or to rule out the suspicion of infection with Bonamia ostreae

When a suspicion of infection with Bonamia ostreae is required to be confirmed or ruled out in accordance with F1Part 4 of the Aquatic Animal Health Regulations, the following inspection, sampling and testing procedure shall be complied with:

The official investigation shall include at least one sampling of 30 molluscs of susceptible species if the suspicion is based on a mortality report, or if not 150 molluscs of susceptible species after the beginning of the transmission period of Bonamia ostreae. When the transmission period is not known, the sampling shall begin in the winter or at the beginning of spring. The samples shall be tested using the diagnostic methods set out in point (i) following the detailed diagnostic methods and procedures set out in Section I of Part 5 of Annex II.

1. (i)

   the presence of Bonamia ostreae shall be considered as confirmed when a positive result by histopathology, tissue imprints or in situ hybridisation is combined with a positive result by PCR completed by sequencing in accordance with the approved methods and procedures set out in Part 5 of Annex II;

2. (ii)

   the suspicion of the presence of infection with Bonamia ostreae shall be ruled out, if those tests reveal no further evidence of the presence of Bonamia ostreae.