Distribution, seasonality, and hosts of the Rocky Mountain wood tick in the United States

Publication Type:

Journal Article

Authors:

James, Angela M.; Freier, Jerome E.; Keirans, James E.; Durden, Lance A.; Mertins, James W.; Schlater, Jack L.

Source:

Journal of Medical Entomology, Entomological Society of America, Volume 43, Issue 1, p.17-24 (2006)

Call Number:

A06JAM01IDUS

URL:

http://naldc.nal.usda.gov/download/6848/PDF

Keywords:

Dermacentor andersoni, Dermacentor variabilis, Rocky Mountain wood tick

Abstract:

Anaplasma marginale Theiler is a tick-borne pathogen that causes anaplasmosis in cattle. There are ≈20 tick species worldwide that are implicated as vectors of this pathogen. In the United States, Dermacentor andersoni Stiles and Dermacentor variabilis (Say) are the principal vectors. The risk of transmission of anaplasmosis to cattle has been largely based on the distribution of D. andersoni in the United States. The authors developed a centralized geographic database that incorporates collection records for D. andersoni from two large national databases. The geographic records in each database and postings from MEDLINE and AGRICOLA were reviewed to produce a national county-level distribution map based on a total of 5,898 records. The records spanned the period from 1903 through 2001, with the majority between 1921 and 1940. Populations of D. andersoni were recorded from 267 counties in 14 states and were distinguished as either established or reported. One hundred eighty counties were found with established populations of D. andersoni and 87 counties with reported occurrences in 14 states; the majority of established populations reported were from Montana, Idaho, and Oregon. D. andersoni populations in the United States currently extend from the western portions of Nebraska and the Dakotas westward to the Cascade Mountains and from the northern counties of Arizona and New Mexico northward to the Canadian border. The data will be useful for identifying regions at increased risk of acquiring anaplasmosis in the United States. Based upon the database collection records, a summary of recorded hosts for D. andersoni is provided, as well as comments on its seasonal occurrence.