From the Guidelines
Tick-borne illnesses should be treated with doxycycline as the first-line antibiotic, with a dosage of 100 mg twice per day for at least 3 days after fever subsides and until evidence of clinical improvement is noted, with a minimum treatment course of 5-7 days. The diagnosis and management of tickborne rickettsial diseases, including Rocky Mountain spotted fever and other spotted fever group rickettsioses, ehrlichioses, and anaplasmosis, are crucial to prevent severe illness and death 1.
Key Considerations
- Doxycycline is the treatment of choice for suspected tickborne rickettsial diseases in adults and children, with a recommended dosage of 2.2 mg/kg of body weight per dose twice per day for children weighing less than 100 lbs (45 kg) 1.
- Early empiric antibacterial therapy can prevent severe disease and death, and treatment should be extended to 10 days if concurrent Lyme disease is suspected 1.
- Patients with evidence of organ dysfunction, severe thrombocytopenia, mental status changes, or the need for supportive therapy should be hospitalized, while others can be treated on an outpatient basis with oral medication and close follow-up 1.
Prevention and Diagnosis
- Prevention is the best approach, including using insect repellents containing DEET (20-30%), wearing protective clothing, checking for ticks after outdoor activities, and removing attached ticks promptly with fine-tipped tweezers.
- If symptoms like fever, rash, fatigue, muscle aches, or joint pain develop within a few weeks after a tick bite, medical attention should be sought immediately.
- Recognition of key epidemiologic features and clinical manifestations of tickborne rickettsial diseases is critical for early diagnosis and treatment, as early signs and symptoms can be nonspecific or mimic other illnesses 1.
From the Research
Tick-Borne Illnesses
- Tick-borne diseases in the United States include Rocky Mountain spotted fever, Lyme disease, ehrlichiosis, tularemia, babesiosis, Colorado tick fever, and relapsing fever 2
- These diseases can be prevented by early removal of attached ticks, as 24 to 48 hours of attachment are required for infection to occur 2
- Ticks can transmit bacterial, protozoal, and viral infections to humans, and specific therapy is available for several of these infections 3
Symptoms and Diagnosis
- Patients with tick-borne diseases often present with flu-like symptoms, and a petechial rash or erythema migrans can be indicative of the specific disease 2, 4
- Lyme disease typically presents with an erythema migrans rash in 70% to 80% of patients, while Rocky Mountain spotted fever presents with a macular rash that becomes petechial 4
- Diagnosis is often made clinically, and treatment should not be delayed for laboratory confirmation if clinical findings are suggestive of tick-borne disease 2, 4
Treatment
- Doxycycline is the antimicrobial treatment of choice for several tick-borne diseases, including Rocky Mountain spotted fever, human monocytic ehrlichiosis, and human granulocytic ehrlichiosis 3, 5
- Amoxicillin or doxycycline can be used to treat early localized Lyme disease, while intravenous ceftriaxone or penicillin G may be required for late or severe disease 6
- Prophylactic treatment with single-dose doxycycline (200 mg orally) can be used in selected patients to prevent Lyme disease 6