Rocky Mountain Spotted Fever
Rocky Mountain spotted fever (RMSF) is a potentially fatal bacterial tickborne disease. The organism that causes the illness, Rickettsia rickettsii, is found in North and South America. Several varieties of tick transmit RMSF, the symptoms of which are evident 2 to 14 days after the illness is contracted. Because the disease must be treated during the first few days to avoid serious complications, and because diagnostic tests take too long to be helpful, physicians most often prescribe the necessary medication on medical history and clinical data alone.
Symptoms of RMSF
The early symptoms of RMSF may mimic the symptoms of many other illnesses. Typical symptoms include:
- Fever
- Headache
- Bloodshot eyes
- Abdominal pain
- Nausea and vomiting
- Muscle aches
- Small, flat, non-itchy rash
The rash may develop as late as 5 days after the fever and about 10 percent of patients with RMSF never develop it at all. Children are more likely to present with abdominal pain, sore throat, rash and gastrointestinal symptoms than adults, and less likely to report having a headache. Children are also more likely to have symptoms of cognitive impairment.
Diagnosis of RMSF
Diagnosis of this disease can be tricky, particularly because early treatment is necessary to prevent fatality and the symptoms of RMSF are so general. If medication is not administered, the patient can die within 8 days of disease onset. Unfortunately, at present there is no diagnostic test that provides results quickly enough to be helpful in making treatment decisions.
To make the situation even more troublesome, not all patients develop all the symptoms and some may have different combinations of symptoms than others. Physicians suspect this illness based in part on medical history, especially if that history includes details about the patient having recently been in areas where ticks are prevalent. Because tick bites are not usually painful and half of the patients infected have no recollection of having been bitten, this is very important.
Certain blood tests may suggest RMSF, such as a low platelet count, low sodium levels, or elevated liver enzymes. These abnormal levels, however, are not present in all patients. The definitive test for the bacteria that cause RMSF is often negative until later, so it is always safer to prescribe treatment than to withhold it.
Treatment of RMSF
If there is any reasonable suspicion of RMSF, patients are treated with the antibiotic doxycycline even before a rash appears. While some patients may recover quickly with oral administration of the medication, more severe cases may require intravenous administration. In some cases, intensive hospital care is required.
Prevention of RMSF
The best treatment for RMSF is prevention of tick bites. There are several measures that can be taken to avoid getting tick bites. These include:
- Avoiding wooded areas or dense grass
- Using tick repellent containing at least 20 percent DEET
- Wearing light-colored clothing, including socks
- Tucking pants into socks when hiking
- Using tick repellent and spraying permethrin on clothing
- Showering or bathing after outdoor activities
- Checking the body for ticks after spending time outdoors
- Examining pets, clothing and camping gear for ticks
- Tumbling clothes in the dryer at high heat for 1 hour
Because RMSF is a serious disease that may not be diagnosed early enough for successful treatment, these precautionary measures are essential for anyone living in areas where the disease is endemic.