Rocky Mountain spotted fever

Rocky Mountain spotted fever
Other namesBlue disease,[1] Brazilian spotted fever, Tobia fever, new world spotted fever, tick-borne typhus fever, São Paulo fever[2]
Petechial rash on the arm caused by Rocky Mountain spotted fever
SpecialtyInfectious disease
SymptomsEarly: Fever, headache[3]
Later: Rash[3]
ComplicationsHearing loss, loss of limbs[3]
Usual onset2 to 14 days after infection[2]
Duration2 weeks[2]
CausesRickettsia rickettsii spread by ticks[4]
Diagnostic methodBased on symptoms[5]
Differential diagnosisZika fever, dengue, chikungunya, Rickettsia parkeri rickettsiosis, Pacific Coast tick fever, rickettsialpox[6][7]
TreatmentDoxycycline[8]
Prognosis0.5% risk of death[6]
Frequency< 5,000 cases per year (USA)[6]

Rocky Mountain spotted fever (RMSF) is a bacterial disease spread by ticks.[9] It typically begins with a fever and headache, which is followed a few days later with the development of a rash.[3] The rash is generally made up of small spots of bleeding and starts on the wrists and ankles.[10] Other symptoms may include muscle pains and vomiting.[3] Long-term complications following recovery may include hearing loss or loss of part of an arm or leg.[3]

The disease is caused by Rickettsia rickettsii, a type of bacterium that is primarily spread to humans by American dog ticks, Rocky Mountain wood ticks, and brown dog ticks.[4] Rarely the disease is spread by blood transfusions.[4] Diagnosis in the early stages is difficult.[5] A number of laboratory tests can confirm the diagnosis but treatment should be begun based on symptoms.[5] It is within a group known as spotted fever rickettsiosis, together with Rickettsia parkeri rickettsiosis, Pacific Coast tick fever, and rickettsialpox.[6]

Treatment of RMSF is with the antibiotic doxycycline.[8] It works best when started early and is recommended in all age groups, as well as during pregnancy.[8] Antibiotics are not recommended for prevention.[8] Approximately 0.5% of people who are infected die as a result.[6] Before the discovery of tetracycline in the 1940s, more than 10% of those with RMSF died.[6]

Fewer than 5,000 cases are reported a year in the United States, most often in June and July.[6] It has been diagnosed throughout the contiguous United States, Western Canada, and parts of Central and South America.[10][2] Rocky Mountain spotted fever was first identified in the 1800s in the Rocky Mountains.[10]

  1. ^ Pedro-Pons, Agustín (1968). Patología y Clínica Médicas. Vol. 6 (3rd ed.). Barcelona: Salvat. p. 345. ISBN 978-84-345-1106-4.
  2. ^ a b c d "Pathogen Safety Data Sheets: Infectious Substances – Rickettsia rickettsii". Government of Canada. Public Health Agency of Canada. 7 January 2011. Retrieved 19 January 2019.
  3. ^ a b c d e f "Signs and Symptoms Rocky Mountain Spotted Fever (RMSF)". CDC. 26 October 2018. Retrieved 19 January 2019.
  4. ^ a b c "Transmission and Epidemiology Rocky Mountain Spotted Fever (RMSF)". CDC. 26 October 2018. Retrieved 19 January 2019.
  5. ^ a b c "Clinical and Laboratory Diagnosis Rocky Mountain Spotted Fever (RMSF)". CDC. 26 October 2018. Retrieved 19 January 2019.
  6. ^ a b c d e f g "Epidemiology and Statistics Rocky Mountain Spotted Fever (RMSF)". CDC. 26 October 2018. Retrieved 19 January 2019.
  7. ^ Cite error: The named reference Al2017 was invoked but never defined (see the help page).
  8. ^ a b c d "Treatment Rocky Mountain Spotted Fever (RMSF)". CDC. 26 October 2018. Retrieved 19 January 2019.
  9. ^ "Rocky Mountain Spotted Fever (RMSF)". CDC. 15 November 2018. Retrieved 20 January 2019.
  10. ^ a b c Koyfman, Alex; Long, Brit; Gottlieb, Michael (2018-07-01). "The Evaluation and Management of Rocky Mountain Spotted Fever in the Emergency Department: a Review of the Literature". Journal of Emergency Medicine. 55 (1): 42–50. doi:10.1016/j.jemermed.2018.02.043. ISSN 0736-4679. PMID 29685474. S2CID 23489868.