UC Davis

Red pandas (Ailurus fulgens) are a globally endangered small carnivoran species and subjects of a robust ex situ conservation effort that includes animals housed in zoos. In 2018, red panda amdoparvovirus (RPAV) was discovered by metagenomics analyses of tissues from two geriatric red pandas, and in one case it was associated with significant lesions. Because RPAV was discovered in a single zoo cohort, it was unclear whether these infections represented a widely distributed, enzootic virus of red pandas or a localized 'spillover' from a different host species into this collection. The first goal of this study was to estimate the prevalence of RPAV in US zoos. The authors amplified RPAV from feces of 104 individual red pandas from 37 US zoos, and the virus was detected in 52/104 samples (50.0%). Next, to establish persistence of infection in individual animals, the authors tested serial samples in a single cohort over a 4.5-yr period, and virus was consistently shed by infected animals throughout the sampling period. Finally, full viral coding sequences were amplified and sequenced from three cases, and partial sequences of both the nonstructural and capsid genes were obtained for an additional 19 cases. RPAV is a genetically diverse but monophyletic viral species, and multiple viral lineages are present in US zoo-housed red pandas. The authors do not know how red pandas were originally infected, but RPAV is very common in red pandas in the United States, and infections are persistent-presumably for the lifetime of the animal.