Tick Disease in Arkansas: Causes, Symptoms and Treatment
by Thomas Harris, MD
Fellow of the Academy of Wilderness Medicine
Urgent Care Physician at MediServe Walk-In Clinic
In Arkansas, we have a number of tickborne illnesses and we see a number of cases at MediServe Walk-In Clinic during the summer. Patients often have questions about tickborne diseases, the symptoms and treatments. As a Fellow of the Academy of Wilderness Medicine, I have studied tickborne illness and work closely with the State of Arkansas on the latest information on tick disease in Arkansas.
#1: Spotted Fever
The most common tickborne disease in our area is Spotted Fever, which was previously known as Rocky Mountain Spotted Fever (RMSF), with almost 4000 proven cases in the last five years (or about 800 cases a year primarily in Northwest Arkansas).
Cause: Rickettsia rickettsii is a bacteria that causes the disease. It is transmitted after the tick has been attached 6-10 hours.
Symptoms: About 25-30% of the infected people will not remember a tick bite. Infected patients become symptomatic 3-14 days after the bite with headache and fever as the key symptoms. Other symptoms include fatigue, muscle aches, joint pain and nausea. Rash occurs in approximately 88 to 90 percent of patients, but is uncommonly seen at beginning. Most patients with RMSF develop a rash between the third and fifth days of illness. The hallmark of RMSF is a blanching red rash with flat lesions (1 to 4 mm in size) that become petechial over time.
Diagnosis and Treatment A presumptive diagnosis of RMSF is initially made based upon consistent clinical signs and symptoms in the appropriate epidemiologic setting (i.e. Northwest Arkansas). Treatment should be initiated within five days of symptom onset. Thus, most patients will require empiric therapy since RMSF can rarely be confirmed or disproved in its early phase. Treatment is Doxycycline 100 mg twice a day, even for children.
The second most common is Ehrlichiosis with nearly 900 cases in the past five years in Arkansas.
Cause: When discussing tickborne illnesses Anaplasmosis is often included with it. The two most important species to infect humans include Ehrlichia chaffeensis (which is named for Fort Chaffee where it was discovered)the causative agent of human monocytic ehrlichiosis (HME), and A. phagocytophilum, the agent of human granulocytic anaplasmosis (HGA).
Symptoms: Most ehrlichial diseases have an incubation period of five to 14 days. Most patients have a fever. Nonspecific symptoms such as fatigue, muscle aches, headache, and chills occur in over two-thirds of cases, while nausea, vomiting, joint pain, and cough occur in 25 to 50 percent. Rash, which can be red and or raised, occurs in a minority of patients.
Diagnosis and Treatment: Treatment is more likely to be effective if started early in the course of disease. Diagnostic tests based on the detection of antibodies will frequently be negative in the first 7-10 days of illness. Treatment is Doxycycline 100 mg twice a day, even for children.
The third most common tick disease in Northwest Arkansas is tularemia with 160 cases over the past five years.
Cause: Tularemia is the zoonotic infection caused by Francisella tularensis.
Symptoms: Tularemia usually has an abrupt or rapid onset of nonspecific systemic symptoms, including some combination of fever, chills, loss of appetite, and fatigue. Patients also may complain of headache, soreness in the chest or muscles, abdominal pain, vomiting, or diarrhea; plus it has six different forms it can take depending on the site of inoculation.
Diagnosis and Treatment: Preferred oral agents in adults areciprofloxin or doxycycline for mild to moderate cases.
Other Tick Diseases
Lyme disease is extremely rare in Arkansas, with only two cases confirmed. However, we have a tickborne illness called STARI, which stands for Southern Tick Associated Rash and Illness.
Cause and Symptoms: STARI is characterized by the presence of a rash typical of erythema migrans (EM) and mild flu-like symptoms that was associated with a bite by the Lone Star tick (Amblyomma americanum). The median time from tick detection to onset of rash was 12 days with a range of 2 to 21 days.
Diagnosis and Treatment: When patients residing in Arkansas where Lyme disease is not found develop skin lesions typical of erythema migrans and when a history of a recent tick bite is either elicited or thought to be possible, a 10-day course of doxycycline 100 mg orally twice daily should be prescribed.
For more information on tick disease in Arkansas, visit the Arkansas Department of Health website.
If you have any of these symptoms or suspect you may have a tickborne illness, talk to your doctor or seek urgent care as soon as possible.
Dr. Thomas Harris is Board Certified in Family Medicine and provides urgent care at MediServe Walk-In Clinic in Fayetteville where he often sees patients with tickborne illness. Dr. Harris is a Fellow of the Academy of Wilderness Medicine.