Rocky Mountain spotted fever can be spread to humans through the bite of an infected tick. The disease itself is caused by the bacterium R. rickettsii, which belongs to a genus of bacteria that cause typhus and other forms of spotted fevers. Rocky Mountain spotted fever was discovered in 1906 by Howard Ricketts, who later died of rodent-carried typhus, a related disease.
Although the majority of cases of the disease are reported in North Carolina, Tennessee, Oklahoma, Arkansas and Missouri, Rocky Mountain spotted fever can occur in virtually every US state.
Rocky Mountain spotted fever symptoms
Several species of ticks can spread the disease, including American dog ticks, which are found east of the Rocky Mountains and on the Pacific Coast; Rocky Mountain wood ticks, found in Rocky Mountain states; and brown dog ticks, found worldwide.
Rocky Mountain spotted fever can present at first like a number of common illnesses, with symptoms that can include fever, headache and gastrointestinal illness. Two to five days after symptoms begin, an individual might develop a rash.
According to Jo Foellmi, a public health nurse for La Crosse County, Wisconsin, the woman who recentlycontracted the disease was probably bitten by an American dog tick while she and her family were camping. She developed nausea, vomiting, diarrhea and a stomachache in addition to a rash, the telltale sign of the illness.
To complicate matters, up to 40% of people who contract Rocky Mountain spotted fever don’t remember being bitten by a tick, so it is important to monitor symptoms and tell a health provider if you have been in places where ticks are common, such as heavily wooded areas with tall grass.
Since ticks are most active in the summer, most cases of the disease are reported between May and August.
Treatment and prevention
The antibiotic doxycycline is the best treatment for Rocky Mountain spotted fever for children and adults who have been infected. Doxycycline treats all tick-borne pathogens, many of which present similarly at first, Sexton said.
Doxycycline is most effective when used in the first five days of illness.
Since there is no vaccine for Rocky Mountain spotted fever, the best way to prevent the disease is to avoid areas where ticks are common, check for ticks on your clothing or your body and use insect repellent that contains DEET.
“This is an issue of public awareness,” Foellmi said, adding that people who spend time outside should check themselves, family members and pets for ticks and that hikers should stay on the trail to avoid encountering ticks.
Most ticks aren’t infected with the bacterium that causes spotted fever, so a tick bite without any symptoms is not cause for concern, Sexton said.
News credit : Cnn