TY - JOUR
T1 - Viruses in unexplained encephalitis cases in American black bears (Ursus americanus)
AU - Alex, Charles E.
AU - Fahsbender, Elizabeth
AU - Altan, Eda
AU - Bildfell, Robert
AU - Wolff, Peregrine
AU - Jin, Ling
AU - Black, Wendy
AU - Jackson, Kenneth
AU - Woods, Leslie
AU - Munk, Brandon
AU - Tse, Tiffany
AU - Delwart, Eric
AU - Pesavento, Patricia A.
N1 - Funding Information:
The authors received no specific funding for this work. We thank Vorthon Sawasong for helpful discussions, and Carl Lackey and Drs. Terza Brostoff and Steven Kubiski for reviewing the manuscript. We thank the field and wildlife health staff at CDFW and NDOW for their technical and logistical support in handling these cases.
PY - 2020/12
Y1 - 2020/12
N2 - Viral infections were investigated in American black bears (Ursus americanus) from Nevada and northern California with and without idiopathic encephalitis. Metagenomics analyses of tissue pools revealed novel viruses in the genera Circoviridae, Parvoviridae, Anelloviridae, Polyomaviridae, and Papillomaviridae. The circovirus and parvovirus were of particular interest due to their potential importance as pathogens. We characterized the genomes of these viruses and subsequently screened bears by PCR to determine their prevalence. The circovirus (Ursus americanus circovirus, UaCV) was detected at a high prevalence (10/16, 67%), and the chaphamaparvovirus (Ursus americanus parvovirus, UaPV) was found in a single bear. We showed that UaCV is present in liver, spleen/lymph node, and brain tissue of selected cases by in situ hybridization (ISH) and PCR. Infections were detected in cases of idiopathic encephalitis and in cases without inflammatory brain lesions. Infection status was not clearly correlated with disease, and the significance of these infections remains unclear. Given the known pathogenicity of a closely related mammalian circovirus, and the complex manifestations of circovirus-associated diseases, we suggest that UaCV warrants further study as a possible cause or contributor to disease in American black bears.
AB - Viral infections were investigated in American black bears (Ursus americanus) from Nevada and northern California with and without idiopathic encephalitis. Metagenomics analyses of tissue pools revealed novel viruses in the genera Circoviridae, Parvoviridae, Anelloviridae, Polyomaviridae, and Papillomaviridae. The circovirus and parvovirus were of particular interest due to their potential importance as pathogens. We characterized the genomes of these viruses and subsequently screened bears by PCR to determine their prevalence. The circovirus (Ursus americanus circovirus, UaCV) was detected at a high prevalence (10/16, 67%), and the chaphamaparvovirus (Ursus americanus parvovirus, UaPV) was found in a single bear. We showed that UaCV is present in liver, spleen/lymph node, and brain tissue of selected cases by in situ hybridization (ISH) and PCR. Infections were detected in cases of idiopathic encephalitis and in cases without inflammatory brain lesions. Infection status was not clearly correlated with disease, and the significance of these infections remains unclear. Given the known pathogenicity of a closely related mammalian circovirus, and the complex manifestations of circovirus-associated diseases, we suggest that UaCV warrants further study as a possible cause or contributor to disease in American black bears.
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U2 - 10.1371/journal.pone.0244056
DO - 10.1371/journal.pone.0244056
M3 - Article
C2 - 33332429
AN - SCOPUS:85098126662
VL - 15
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 12
M1 - e0244056
ER -