Post Exposure Treatment With Doxycycline for the Prevention of Relapsing Fever
Post Exposure Treatment With Doxycycline for the Prevention of Relapsing Fever
Abstract Background Tick-Borne Relapsing Fever (TBRF) is an acute febrile illness. In Israel,
 TBRF is caused by Borrelia persica and is transmitted by Ornithodoros tholozani ticks. We
 examined the safety and efficacy of a post exposure treatment policy to prevent TBRF.

 Methods In a double blind, placebo controlled trial 93 healthy volunteers with suspected tick
 exposure (51 with bite signs and 42 contacts) were randomly assigned to receive either
 Doxycycline (200 mg for the first day and 100mg/d for 4 days) or placebo, approximately 2
 days after contact. Blood smears were examined for Borrelia at inclusion and during fever
 rise. Serology for Lyme disease cross- reactivity and PCR for Borrelia GlpQ gene were also
 performed. Cases of TBRF were defined as subjects having fever and a positive blood smear.
Inclusion Criteria:

 -  suspected exposure to tick-borne relapsing fever

 -  after returning from field exercise in a tick-borne relapsing fever infected area

 -  having a tick bite or staying in field in close proximity to a subject with tick bite
 sign

 Exclusion Criteria:

 -  known sensitivity to tetracycline or doxycycline

 -  febrile illness on recruitment