A SEROLOGIC AND POLYMERASE CHAIN REACTION SURVEY OF EQUINE HERPESVIRUS IN BURCHELL'S ZEBRAS (EQUUS QUAGGA), HARTMANN'S MOUNTAIN ZEBRAS (EQUUS ZEBRA HARTMANNAE), AND THOMSON'S GAZELLES (EUDORCAS THOMSONII) IN A MIXED SPECIES SAVANNAH EXHIBIT

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): infection with Equine Herpesvirus-1

Equine Herpesvirus-1 infection has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of: Article 7 on disease profile and impacts, Article 5 on the eligibility of the disease to be listed, Article 9 for the categorisation of the disease according to disease prevention and control measures as in Annex IV and Article 8 on the list of animal species related to Equine Herpesvirus-1 infection. The assessment has been performed following a methodology composed of information collection and compilation, and expert judgement on each criterion at individual and collective level. The outcome is the median of the probability ranges provided by the experts, which indicates whether the criterion is fulfilled (66-100%) or not (0-33%), or whether there is uncertainty about fulfilment (33-66%). For the questions where no consensus was reached, the different supporting views are reported. According to the assessment performed, Equine Herpesvirus-1 infection can be considered eligible to be listed for Union intervention according to Article 5 of the Animal Health Law with 33-90% certainty. According to the criteria as in Annex IV of the AHL related to Article 9 of the AHL for the categorisation of diseases according to the level of prevention and control, it was assessed with less than 1% certainty that EHV-1 fulfils the criteria as in Section 1 (category A), 1-5% for the criteria as in Section 2 (category B), 10-66% for the criteria as in Section 3 (category C), 66-90% for the criteria as in Section 4 (category D) and 33-90% for the criteria as in Section 5 (category E). The animal species to be listed for EHV-1 infection according to Article 8(3) criteria are the species belonging to the families of Equidae, Bovidae, Camelidae, Caviidae, Cervidae, Cricetidae, Felidae, Giraffidae, Leporidae, Muridae, Rhinocerontidae, Tapiridae and Ursidae.

SURVEY FOR EQUINE HERPESVIRUSES IN POLAR BEARS ( URSUS MARITIMUS) AND EXOTIC EQUIDS HOUSED IN US AZA INSTITUTIONS

Infection by equine herpesvirus (EHV) strains (EHV-1, EHV-9) in ursid species, including polar bears ( Ursus maritimus), has been associated with neurological disease and death. A serosurvey of captive exotic equid and polar bear populations in US Association of Zoos and Aquaria institutions was performed to determine the prevalence of EHV strains using quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) tests. Equid species surveyed included zebra ( Equus spp.), Przewalski's wild horse ( Equus ferus przewalskii), Persian onager ( Equus hemionus), and Somali wild ass ( Equus africanus somaliensis). A questionnaire regarding husbandry and medical variables was distributed to institutions housing polar bears. No polar bears tested positive for EHVs on qPCR of blood or nasal swabs. No exotic equids tested positive for EHVs on qPCR of blood, but two exotic equids ( n = 2/22; 9%) tested positive for EHVs on qPCR of nasal swabs. On ELISA, polar bears infrequently were positive for EHV-1 ( n = 5/38; 13%). Exotic equids were positive for EHV-4 on ELISA more frequently ( n = 30/43; 70%) than for EHV-1 ( n = 8/43; 19%). Nine institutions submitted samples from both exotic equids and polar bears, two of which had both exotic equids and polar bears positive for EHVs by ELISA. Each of these institutions reported that the polar bear and exotic equid exhibits were within 80 m of each other and that risk factors for fomite transmission between exhibits based on husbandry practices were present. One institution that did not house exotic equids had a polar bear test positive for EHV-1 on ELISA, with no history of exposure to exotic equids. Further testing of captive polar bears and exotic equids is recommended, as is modification of husbandry practices to limit exposure of polar bears to exotic equids.