A93.8
DESCRIPTION
Tick-borne infection due to R. conorii, acquired from dogs, or R. africae, acquired from cattle and game. The hallmark of tick bite fever is the eschar, a round black lesion ± 5 mm in diameter with an inflammatory halo, occurs in about two thirds of patients with R. conorii and in most cases of R. africae infection, where multiple eschars are common. A rash develops on about the third day of illness in about two thirds of patients with R. conorii and in fewer cases of R. africae infection. In R. conorii infection the rash is maculopapular and involves the palms and soles. In R. africae infection the rash is sparse and may be vesicular. Headache is a prominent symptom.
MEDICINE TREATMENT
- Doxycycline, oral, 100 mg 12 hourly, for at least 3 days after the fever subsides with clinical improvement.
- Total duration of treatment is 7 days.
In pregnancy: O98.5+(A93.8)
- Azithromycin, oral, 500 mg 12 hourly for 3 days.
- In severe cases, initiate therapy with 1–2 days of doxycycline.
For the rare patient unable to take oral therapy:
Total duration of therapy: 7 days.
- Ciprofloxacin, IV, 400 mg 8 hourly.
Note: This is inferior to doxycycline and oral doxycyclineshould be commenced as soon as possible.
REFERRAL
Tick bite fever responds rapidly to treatment and fever persisting for >48 hours after initiation of treatment should prompt consideration of an alternative or additional diagnosis.