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What is Rocky Mountain Spotted Fever


Rocky Mountain Spotted Fever is a serious and often severe illness caused by the organism called “Ricketssia ricketsii”. This spiral shaped organism is large relative to typical bacteria and belongs to the group of similarly shaped organisms called spirochetes (other spirochetal illnesses include the tick-borne Lyme disease and the sexually transmitted disease syphilis). Unlike these other two illnesses, however, Rocky Mountain Spotted Fever is unique in that it may cause rapid and severe illness.

Various ticks transmit the disease to humans (Dog tick, wood tick, Lone Star Tick). Nonspecific symptoms (i.e. found in many other illnesses also) include fever, headache, muscle ache, nausea, vomiting, and diarrhea. A characteristic rash may develop, often beginning on the wrists and ankles and spreading centrally to the chest and back area. The rash often involves the palms and soles, helping to suggest the diagnosis (very few illnesses cause rashes on the palms and soles–syphilis, and hand-foot-mouth disease are two others). Illness may involve many organ systems, including the brain, heart, lungs, and bone marrow.

In severe illness, shock and death may ensue. The outcome is usually worse if treatment has been delayed. Delay in treatment is more likely to occur when the illness is not suspected, as may occur when the characteristic rash is not present on the victim, when there is no known tick bite, and in areas where the illness is rarely seen. If the diagnosis is suspected, treatment begin immediately, as the diagnostic tests often take a few days to come back from the laboratory.

Treatment is with specific antibiotics, most commonly doxycycline, and other specific supportive care as needed.