Relapsing Fever: Ornithodoros hermsi a Vector in Colorado

Publisher Website
Google Scholar
Abstract
Relapsing fever has occurred sporadically in Colorado since 1915 but there was no information concerning a tick vector until Sept. 1938, when 51 O. hermsi were collected from a decaying Douglas fir stump in northern Park County about 40 miles southwest of Denver, where 2 cases had occurred earlier in the summer. Spiro-chetes were not recovered from this lot. In June, 1939 an additional 213 O. hermsi were collected from another decaying stump in the same locality. 204 of these were tested in 20 groups of 10 each and one group of 4 by feeding on young white rats. Spirochetes appeared in the peripheral blood of 3 rats. Progeny from these ticks also proved infective. Heretofore this tick has been known only in parts of California and northern Idaho. Its presence east of the Continental Divide at least suggests its sporadic occurrence in a considerable part of the Rocky Mountain region. The only other record of a spirochete-carrying species of O. in Colorado is that of a single nymph of O. parkeri from a group of 8 prairie dogs (Cynomys sp.) collected in 1938 in Moffat County (northwestern Colorado).

This publication has 1 reference indexed in Scilit: