| prevalence of rickettsia species in dermacentor variabilis ticks from ontario, canada. | relatively little is known about the prevalence of rickettsial species in dermacentor ticks in eastern canada. in this study, dermacentor ticks from the province of ontario, canada, were tested for the presence of spotted fever group rickettsial (sfgr) species, coxiella burnetii and francisella tularensis. rickettsia rickettsii was not detected in any ticks tested, but r. montanensis was detected at a prevalence of 2.2% in d. variabilis (17/778). two other sfgr species, r. parkeri and candidatus ... | 2016 | 27318438 |