Nonpathogenic rickettsias related to the spotted fever group isolated from ticks, Dermacentor variabilis
and Dermacentor andersoni from eastern Montana.
Only collected adults of Dermacentor variabilis
were used in this study.
428 ticks of Amblyomma americanum and Dermacentor variabilis
Numbers presented are prevalence (percent of hosts infested) and numbers of males (M), Females (F) and Nymphs(N) col-lected for each ectoparasite species Virginia Ectoparasite species opossum Raccoon Tick: Dermacentor variabilis
83%, 42M, 44F 100%, 41M.
Comparative vector competence of Dermacentor variabilis
and Ixodes scapularis (Acari: Ixodidae) for the agent of human granulocytic ehrlichiosis.
Sin embargo, en una investigacion  se identifica la especie Dermacentor variabilis
en perros de Venezuela, la cual no fue encontrada en el presente reporte.
This vast distribution is a result of the ticks that serve as vector and reservoir of the disease: Dermacentor variabilis
(commonly known as the American dog tick) in the eastern United States and Dermacentor andersoni (commonly known as the Rocky Mountain wood tick) in the western United States.
Three species of ticks, including Amblyomma americanum, Dermacentor variabilis
, and Ixodes scapularis were collected from animals as well as from public areas by flagging vegetation in 25 different counties in order to determine areas of greatest risk.
In the eastern United States, the usual vector of Rocky Mountain spotted fever (RMSF) is the American dog tick, Dermacentor variabilis
, while in the West the Rocky Mountain wood tick, Dermacentor andersoni, predominates.
The American dog tick or wood tick, Dermacentor variabilis
(Say) is an eastern species, known in Canada from Nova Scotia to south central Saskatchewan.
2,6-Dichlorophenol has so far been the only verified attractant sex pheromone of the American dog tick, Dermacentor variabilis
(Say), and acts to bring members of the mating pair together.
The tick, Dermacentor variabilis
, releases a toxin that interferes with nerve transmission.