Experimental Infection of Raccoons (Procyon lotor) with West Nile Virus

Authors

J. Jeffrey Root, USDA/APHIS/WS National Wildlife Research CenterFollow
Kevin T. Bentler, National Wildlife Research CenterFollow
Nicole M. Nemeth, Colorado State University
Thomas Gidlewski, Colorado State UniversityFollow
Terry R. Spraker, United States Department of Agriculture
Alan B. Franklin, United States Department of AgricultureFollow

Document Type

Article

Date of this Version

2010

Citation

American Journal of Tropical Medicine and Hygiene, 83(4), 2010, pp. 803–807 doi:10.4269/ajtmh.2010.10-0173

Abstract

To characterize the responses of raccoons to West Nile virus (WNV) infection, we subcutaneously exposed them to WNV. Moderately high viremia titers (≤ 10^4.6 plaque forming units [PFU]/mL of serum) were noted in select individuals; however, peak viremia titers were variable and viremia was detectable in some individuals as late as 10 days post-inoculation (DPI). In addition, fecal shedding was prolonged in some animals (e.g., between 6 and 13 DPI in one individual), with up to10^5.0 PFU/fecal swab detected. West Nile virus was not detected in tissues collected on 10 or 16 DPI, and no histologic lesions attributable to WNV infection were observed. Overall, viremia profiles suggest that raccoons are unlikely to be important WNV amplifying hosts. However, this species may occasionally shed significant quantities of virus in feces. Considering their behavioral ecology, including repeated use of same-site latrines, high levels of fecal shedding could potentially lead to interspecies fecal-oral WNV transmission.