Investigations of White -Tailed Deer Infestation by Ixodes Scapularis on the Illinois River, USA

From 1998 to 2003, hunter-killed white-tailed deer (Odocoileus virginianus (Zimmermann)) were inspected for Ixodes scapularis (Say) (Acari: Ixodidae) to ascertain tick establishment along the Illinois River. A county-level study demonstrated that I. scapularis is the predominant tick in the northern portion of the Illinois River, unlike Dermacentor albipictus (Packard) (Acari: Ixodidae) that was most common in the southern part. A geographic information system (GIS) was used in conjunction with spatial statistics to determine the spatial pattern of hunter-killed deer along the river. The results demonstrated that deer are clustered and their distribution is best explained by riverine forest cover. Bivariate and nearest-neighbor spatial analyses indicated that infested deer were more clustered than uninfested deer. Local spatial analyses identified the locations of high and low I. scapularis prevalence clusters. High clusters were found in the northern portion of the river and although low clusters were predominant in the south, some were identified in more northerly locations. High prevalence clusters were associated with alfisol soil texture and dry-mesic upland forests, and situated closer to Castle Rock State Park, the first known site of I. scapularis establishment in Illinois. Individual deer prevalence was also associated with upland dry-mesic forests and proximity to Castle Rock State Park, as well as with loam and gravelly loam soils, entisol and inceptisol soil orders, average temperature for the week prior to the hunt and deer sex and age status. Increasing trends in tick prevalence and intensity, coupled with the identification of new high prevalence clusters, suggest that the geographic range of I. scapularis is expanding south along the Illinois River. The implications of these findings are that I. scapularis distribution in Illinois continues to be dynamic, and that Borrelia burgdorferi and other I. scapularis-borne pathogens may eventually be transmitted around and south of the Peoria metropolitan area. Further entomological and epidemiologic studies are warranted to ascertain human and canine Lyme disease in these areas.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Veterinary Pathobiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Cortinas, Manuel Roberto

Contributors dc:contributor

• Uriel D. Kitron

• Agriculture, Forestry and Wildlife

Language dc:language

eng

Identifier

(MiAaPQ)AAI3301122

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/87635