5-Minute Emergency Consult
Rocky Mountain Spotted Fever
Basics
Description
Rickettsial invasion of small blood vessels:
- Most lethal tick-vector illness in the US
- 25% case fatality ratio if untreated
- Causes direct vascular damage
- Superimposed additional vascular damage/vasculitis due to immunologic phenomena
Etiology
- Acute infection by Rickettsia rickettsii via tick vector:
- Dermacentor andersoni (wood tick) in the western states
- Dermacentor variabilis (dog tick) in the eastern states
- Rhipicephalus sanguineus (brown dog tick) in the southwestern states
- Reported in all states; 1/2 of cases occur in 5 states (NC, SC, TN, OK, AR), as well as parts of Central America and South America
- More common April–September, but can occur any month
- More common in males and in individuals 40–64 yr of age
There's more to see -- the rest of this topic is available only to subscribers.
Citation
Schaider, Jeffrey J., et al., editors. "Rocky Mountain Spotted Fever." 5-Minute Emergency Consult, 7th ed., Wolters Kluwer, 2027. Emergency Central, emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307562/4/Rocky_Mountain_Spotted_Fever_.
Rocky Mountain Spotted Fever. In: Schaider JJJ, Barkin RMR, Hayden SRS, et al, eds. 5-Minute Emergency Consult. Wolters Kluwer; 2027. https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307562/4/Rocky_Mountain_Spotted_Fever_. Accessed July 13, 2026.
Rocky Mountain Spotted Fever. (2027). In Schaider, J. J., Barkin, R. M., Hayden, S. R., Wolfe, R. E., Barkin, A. Z., Shayne, P., & Rosen, P. (Eds.), 5-Minute Emergency Consult (7th ed.). Wolters Kluwer. https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307562/4/Rocky_Mountain_Spotted_Fever_
Rocky Mountain Spotted Fever [Internet]. In: Schaider JJJ, Barkin RMR, Hayden SRS, et al, eds. 5-Minute Emergency Consult. Wolters Kluwer; 2027. [cited 2026 July 13]. Available from: https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307562/4/Rocky_Mountain_Spotted_Fever_.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC
T1 - Rocky Mountain Spotted Fever
ID - 307562
ED - Barkin,Adam Z,
ED - Shayne,Philip,
ED - Rosen,Peter,
ED - Schaider,Jeffrey J,
ED - Barkin,Roger M,
ED - Hayden,Stephen R,
ED - Wolfe,Richard E,
BT - 5-Minute Emergency Consult
UR - https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307562/4/Rocky_Mountain_Spotted_Fever_
PB - Wolters Kluwer
ET - 7
DB - Emergency Central
DP - Unbound Medicine
ER -
