Collaborative wildlife disease outbreak investigation and response at Bells Swamp Victoria, February 2023

In February 2023, a report of morbidity and mortality in waterbirds triggered a collaborative regional wildlife disease outbreak investigation and response, led by Parks Victoria. Triage, rehabilitation and diagnosis of sick and dead birds were undertaken by Zoos Victoria (ZV), Agriculture Victoria, Vets for Compassion, Wildlife Victoria and Melbourne Veterinary School (MVS). The field response focused on collection of sick and dead birds for wildlife welfare, for diagnosis, and to reduce environmental contamination. Botulism was suspected, based on clinical signs and lack of significant gross pathology, and this diagnosis was confirmed by PCR testing. Low pathogenicity avian influenza (LPAI) viruses non H5 or H7 were detected in two birds and ruled out in all in others tested. These incidental, non-clinical LPAI detections are considered part of the natural wild bird virus community in Australia. A number of elements contributed to the collaborative effort. Regional individuals had the necessary connections for reporting, collecting and transporting birds. There was rapid determination by the Victorian Department of Energy, Environment and Climate Action (DEECA) that Parks Victoria, as the land managers, should lead the response. Zoos Victoria provided capacity and expertise in wildlife triage and rehabilitation, and Agriculture Victoria, ZV and MVS were responsible for veterinary management of the response and diagnosis. Field investigation and response were conducted by Parks Victoria, Agriculture Victoria, MVS and veterinary teams from Vets for Compassion and Wildlife Victoria. Wildlife Health Australia (WHA) provided guidance and information, approved National Significant Disease Investigation Program funding and captured the event in the national wildlife health information database. Communication and media were important for community understanding of the event.