Figure 1.

Community risk assessment for brown dog tick–associated RMSF. Communities with free-roaming dogs, high levels of brown dog ticks, and Rickettsia rickettsii in the dog or tick population are considered medium risk for RMSF transmission. Communities with those factors as well as inadequate community knowledge of tick prevention are considered high risk for RMSF transmission. If healthcare provider knowledge of RMSF diagnosis and treatment is also inadequate, the community is also considered high risk for severe illness or death from RMSF. RMSF, Rocky Mountain spotted fever.