Rocky Mountain spotted fever, or RMSF, is a deadly infectious disease caused by the bacteria Rickettsia rickettsii which is transmitted through the bites of infected ticks. Initial symptoms include sudden fever, muscle pain and headache, followed by development of a rash. The disease is notoriously difficult to diagnose from the immediate symptoms, and can be fatal in 30 percent of cases if left untreated, according to MayoClinic.com.
Rickettsia Rickettsii
The pathogen responsible for RMSF is a type of oblong bacteria which resides inside mammalian cells, feeding off of nutrients supplied by the host and proliferating from cell to cell spreading toxic effects, causing potentially lethal complications for the host, according to Todar's Online Textbook of Bacteriology.
Ticks
Transmission of the bacterial pathogen into humans is caused by a variety of dog ticks and wood ticks, which can attach themselves anywhere on the body, but are most commonly found in the hair, genital region and ankles where they feed on the host's blood. The longer the tick remains attached, the greater the chance of the host becoming infected by the disease, according to Centers for Disease Control and Prevention.
RMSF is most prevalent in the summer months when people spend a lot of time outdoors, and when the Rickettsia rickettsia carrying ticks are more active, according to Centers for Disease Control and Prevention.
Rickettsia Rickettsii and Vasculitis
The bacterial pathogen spreads within endothelium cells that line the interior of small to medium-sized blood vessels, leading to inflammation of these vessels in a process known as vasculitis. Progression of vasculitis to the pancreas, stomach, small intestine and colon frequently leads to nausea, vomiting, diarrhea and cramping of abdominal muscles, according to a November 2007 article published in "Emerging Infectious Diseases."
Rickettsia Rickettsii and Blood Clotting
Infection and proliferation of Rickettsia rickettsii within endothelial cells stimulates these cells to produce molecules involved in blood coagulation, leading to the activation of cells known as platelets that are central to this process. These biochemical changes cause a potential lethal deregulation of the normal blood clotting mechanism, in which vessels are much more likely to become blocked or obstructed by clots. Symptoms may vary from organ dysfunction to tissue death, depending on the severity of the disease and position of the cots, according to an April 2005 article published in "Pediatrics in Review."
References
- "Emerging infectious Diseases"; Rocky Mountain spotted fever, Panama; D. Estripeaut, et al.; November 2007
- Todar's Online Textbook of Bacteriology: Rickettsial Diseases, Including Typhus and Rocky Mountain Spotted Fever (page 1)
- "Pediatrics in Review"; Rocky Mountain spotted fever: A Physician's Challenge; S. Razzaq, G. Schutze; April 2005
- MayoClinic.com: Rocky Mountain Spotted Fever
- Centers for Disease Control and Prevention: Diagnosis and Management of Tickborne Rickettsial Diseases
