Doxycycline Effective in Preventing Tick-Borne Fever
Small placebo-controlled study found all subjects with fever were in placebo group
WEDNESDAY, July 12 (HealthDay News) -- Doxycycline was 100 percent effective in preventing tick-borne relapsing fever in a small, placebo-controlled trial of subjects suspected of having a recent tick exposure, according to a report in the July 13 issue of the New England Journal of Medicine.
Tal Hasin, M.D., from the Medical Corps of the Israel Defense Force in Jerusalem, Israel, and colleagues conducted a randomized, double-blind trial of a five-day course of doxycycline to prevent tick-borne relapsing fever (TBRF) caused by Borrelia persica in 93 subjects with suspected tick exposure. The 47 subjects randomized to doxycycline were given a 200 milligram dose the first day and 100 mg per day for the next four days.
There were 26 subjects in both the doxycycline and placebo groups with signs of tick bites, with the remainder in each group having had close contact. All 10 subjects identified by blood smears as having TBRF were part of the placebo group, suggesting the doxycycline treatment was 100 percent effective.
"Treatment with doxycycline is safe and efficacious in preventing TBRF after suspected exposure to ticks in a high-risk environment," the authors conclude. In areas where tick exposure is less frequent, thorough physical examinations for tick bites will help limit the use of doxycycline to those with the greatest likelihood of infection and reduce medication-associated adverse events, they note.