Louse-borne relapsing fever – report of four cases in Switzerland, June-December 2015

BACKGROUND: Louse-borne relapsing fever (LBRF) is a neglected disease that has been restricted to East Africa for many decades. Several cases in refugees from the Horn of Africa have been recently diagnosed in four European countries. CASE PRESENTATION: We report four additional cases of LBRF in asylum seekers from Somalia and Eritrea who presented with fever shortly after arriving in Switzerland during a seven-month period. Multiple spirochetes were visualized on stained blood films which were identified as Borrelia recurrentis by 16S rRNA gene sequencing. All patients recovered after antibiotic treatment with ceftriaxone and/or doxycycline. Concurrent infections (malaria and tuberculosis) were diagnosed in half of our patients. Possible modes of transmission and preventive measures are discussed. CONCLUSIONS: These reported cases highlight the ongoing transmission of LBRF in migrants from East Africa. Diagnosis of LBRF cases and prevention of autochthonous transmission in asylum seeker camps are important steps for the near future.