D3348: Surveillance Study of Avian Keds /Louse Flies (Diptera: Hippoboscidae) and Related Pathogens at a South Carolina zoo

Zoological parks are a vital societal resource that provides conservation education, cultural value, and economic revenue to local and regional communities. Zoos can also provide triage veterinary services to the surrounding area which supports wildlife health. The Riverbanks Zoo and Gardens provide triage for birds of prey injured in South Carolina and parts of North Carolina. From August to December 2023, a surveillance initiative was conducted to collect vectors of public health importance on the Riverbanks property. We specifically targeted a collection of avian keds (Diptera: Hippoboscidae), commonly called louse flies, from wild raptors. Avian keds are known competent pathogen vectors of bacteria, parasites, and viruses, including West Nile virus (WNV), yet their role in WNV disease dynamics is understudied. Ked collections, performed by zoo staff, involved manual extraction from wild raptors originating from surrounding counties undergoing medical care at the zoo. Over the five months, 28 keds were collected from three raptor species (red-tailed hawk, barred owl, and red-shouldered hawk). All 28 keds were identified as Icosta americana, and 29% had Myialges boreali clusters. Real-time PCR (qPCR) testing results from n=13 pools included two positive pools and three inconclusive pools for WNV. The avian ked identification was a significant and novel discovery, as Icosta americana species are understudied vectors in the USA. The results presented are the preliminary data of a pilot study that will continue for 12 calendar months, to obtain comprehensive raptor health reports and sample raptor host saliva for WNV as an alternative transmission measure.