HIGHLY PATHOGENIC AVIAN INFLUENZA VIRUS (H5N8) OUTBREAK IN A WILD BIRD RESCUE CENTER, THE NETHERLANDS: CONSEQUENCES AND RECOMMENDATIONS

Since the emergence of the Goose/Guangdong H5 lineage in 1996 and spillover of highly pathogenic avian influenza (HPAI) from poultry to wild birds, outbreaks have become increasingly frequent in wild birds. The latest outbreak in the Netherlands occurred in the fall-winter of 2020-2021 and was linked to incursions of HPAI H5N8 virus. During the larger national outbreak, wild birds in rehabilitation center "Vogelklas Karel Schot (VKS)" in Rotterdam presented with clinical signs compatible with HPAI, including head shaking, torticollis, and abnormal gait. During an epidemiologic investigation at VKS, water samples from the pools in the enclosures and oropharyngeal and cloacal swabs from 128 birds of different species were analyzed for the presence of H5N8 virus. Forty-five birds and the pool water tested positive for the virus. The outbreak at VKS was likely introduced by one or more infected geese (Anser anser, Anser anser domesticus, Branta leucopsis), after which the virus spread via pool water and with the relocation of infected birds within the center. In principle, such outbreaks are preventable. Recent updates about HPAI to provide guidance to help avoid future incursions of HPAI into wildlife rescue centers are reported.