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Fatal spirochetosis due to a relapsing fever-like Borrelia sp. in northern spotted owl

January 1, 2002

Acute septicemic spirochetosis was diagnosed in an adult male northern spotted owl (Strix occidentalis caurina) found dead in Kittitas County, Washington, USA. Gross necropsy findings included marked enlargement of the liver and spleen and serofibrinous deposits on the serous membranes lining the body cavities and the pericardial and perihepatic sacs. Microscopic observations included macrophage infiltration in the liver and spleen with mild thrombosis and multifocal necrosis, as well as hemorrhage and acute inflammation in the choroid plexus of the brain. No viruses or pathogenic bacteria were isolated from brain, liver, or spleen, and no parasites were found in blood smears or impression smears of the liver. Chlamydial culture attempts were unsuccessful and no chlamydial antibodies were detected in serum. In silver-stained microscopic sections and by transmission electron microscopy of liver, numerous long, thin, spiral-shaped bacteria were seen in the liver, spleen, cerebral ventricles, and within blood vessels in many organs. The organism was identified as a member of the Borrelia genus by sequence analysis of the PCR-amplified 16S rRNA gene. The most closely related species is B. hermsii, an agent of relapsing fever in humans in the western United States. This is the first report of a relapsing fever-related Borrelia in a wild bird.

Citation Information

Publication Year 2002
Title Fatal spirochetosis due to a relapsing fever-like Borrelia sp. in northern spotted owl
DOI 10.7589/0090-3558-38.1.187
Authors N. J. Thomas, J. Bunikis, A.G. Barbour, M. J. Wolcott
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Wildlife Diseases
Index ID 1004111
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center

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